Yes, those are buds. There are buds at every leaf node. The buds in your picture have started to expand and should become some type of new growth soon. The question is whether those buds will become flowers or new branches with leaves. Initially, citrus trees produce only leaf buds. Under certain stress conditions such as cold or drought a leaf bud can differentiate and become a flower bud. Without an exceptionally clear picture of the buds it is difficult to tell whether those buds will become new branches or flowers. Judging from the shape and width of the buds I would guess they will become flowers although it is difficult to tell from the picture.

As long as those weren't where leaves recently (like last couple days) fell from, I'd agree those are buds. Take pics every few days...

You're correct that putting the plastic bag tightly over foliage AND placing it in direct afternoon sunlight will overheat the canopy as well as cause one ore two other mal conditions. I have used the plastic bag technique for very short periods of time, as in after transplant or for indoor trees for a period of a couple weeks. Neither of these were citrus and they were in acquiescence -- not in a growth period. But that's not my expertise.

What if I cover it with saran wrap just in the evening till morning, and then take it off when the sun shines and I'm not going to put it on air tight, there's gonna be gaps for gases to come in and out?

I'm starting to realise that this is probably happening because of the few hours a day of intesee sunshine the tree is getting. The pot is getting way too overheated, because when I touch it during the sunshine it's like touching a cup of tea.
Should I cover the pot with white material, would that help?

What about covering the pot with aluminum foil so that the sun wouldn't overheat the roots? The sun rays would just reflect from the aluminum foil and not get inside, right?

Millet has a couple of threads on root temps, and there are people who cover their pots and are happy with the results outdoors in the summer, but there is a danger for your situation. The heat probably is a problem and can kill roots (Millet has a couple of threads on this), but also look out for low temps when there is no sun on the pot, so the roots work less efficiently and cannot compensate quickly enough to supply the foliage with moisture when the sun hits the leaves. If you have strong sun on the leaves and the roots never warm up because the pot is covered, all of the leaves will fall off.

I cannot stress enough that you need to get a thermometer to really know what is going on in the pot. I got that tip from the other people here, and it has made all of the difference in the world. The air temp and surface temp of the pot can only tell you so much. A little meat thermometer is cheap, and you can leave it in the pot for a while to see what kind of environment your roots are living in. What is the temp in sun, what is the temp when there is no sunshine in that window, and how big of a temperature swing is your tree suffering through?

As an example, I have a larger pot, and thought all was well in full sun, but the thermometer told me the rootball never got above 60 degrees F, even in a 70 degree room, because evaporation kept it cool. All of my leaves were pale and dull, and I had some leaf drop from the strong sun on my leaves and minimal function of the roots due to the lower root temp. I put a heat mat under it to get the roots up to a constant 70F and now the tree is great--all leaves replaced, new growth, glossy dark green leaves, flowering. Your ideal root temp may vary depending on light, ambient temp, humidity, etc., but there will be some temp range your tree will enjoy.

Search for root temps in this forum, and you will see a lot of work by Millet and others.

Good luck.

I did search about root temps, and all I can say is that during the direct sunlight hours on a south facing window the temperature gets about 50C (122F) in the pot (that's my guess without a thermometer), I said it's like touching a cup of tea.
So I know that I want (AND MUST) to cover the pot, and since I had trouble finding white cloth at home I thought if I could cover the pot with aluminum foil for now.
The main question: can I cover the pot with aluminum foil to prevent the rootball from overheating or should I cover it with white cloth? There's no doubt that the rootball gets overheated

I know there was a thread on here about a guy who did make little "skirts" of cloth for his pot, and was happy both with the results and the fact that it looked much better than foil, but I cannot see why foil would not work as a stop gap.

The more I think about it, however, maybe just move the whole tree out of the window for now because the leaves will heat up and you could lose them depending on the shaded temp of the pot is.

Edit--I did see what you said about the temp of the pot feeling like a cup of tea, but I just wanted to raise a concern about going too far the other way if the pot stays too cool. Good luck.

Foil is fine -- it's best to place it loosely and not directly against the container. Foil will help block radiant heat transfer, but once you place it directly against the container you are then allowing it some conductive heat transfer. So the little "skirt" idea, where you attach it to the rim and let it hang, is best. That's what I do when I'm desperate.

We have white trash can liners that can be cut and tied loosely around a pot.

I've put a white pillow case on to the container

But I've read some threads here about winter leaf drop but I still didn't understand what causes it
Could someone, please, write that shortly in something like bullet points?

Millet answered this a while back, here: link

It is not bullet points, but it is filled with good info and some neat anecdotes.