Taking protein supplements restored my hair???

Hi guys. I know I've been lost for some time now and haven't visited the forum, but a lot has happened to me during this time and a lot of things came up unexpectedly.

So last time I was active here, I dyed my hair silver (see first picture). I was impatient with bleaching and stuff, so although the colour turned pretty well, I kinda damaged my hair to the point it became like a chewing gum.
Then I dyed my hair dark pinkish red, close to fuchsia (sadly I didn't take pictures, because I had died it for only a week until the colour washed out for a reason mentioned below).
I still wasn't aware how serious it was until I visited my stylist to do a keratin treatment. As soon as he washed out all the products from my hair, I saw a disaster. My lower parts of long hair were terribly tangled, stretchy and like a spagetti... Well, kinda... He told me my hair might not hold keratin too well, but I insisted on the procedure anyway. All of my colour washed out and I was left with blonde ombre hair (see second attachment).
It actually helped and my decision revived my hair temporarily for at least a month. after that my hair went back to being stretchy. It was the start of July already and I made a decision to just use some conditioners, masks and cut the ends of my hair gradually with time. I just didn't want to chop it all off.
I decided to forget my hair and died it to a light brown shade to give my hair some pigment and also look more natural. (third attachment).

During these 2 months, a lot has changed. I started working out, lost 10 pounds and started taking whey protein supplement regularly. I didn't think about my hair back then, I just had protein deficiency and decided to help my muscles by providing them with additional protein, which I added to milkshakes and cocktails.
It's been 2 months since my lifestyle changed and I also finally dyed my hair darker a bit. (final, forth picture).
I have been counting calories, eating healthy foods, working out and just leading active lifestyle. Protein changed a lot in my body, gave me more energy, decreased my wild appetite, helped my digestive system work better and also took part in normalizing my periods (i.e. making them regular).
I don't know if protein and healthy food worked a miracle or what, but yesterday after washing my hair without using conditioner (i just ran out of conditioner), I realized my hair was not as stretchy and damaged as before. Yes, the ends are still kinda damaged, but the parts where my ombre meets my natural hair is stonger and healthier.

I just wanted yo ask you if anyone knows or has heard about something like this. I still blame protein though, because I haven't been taking biotin or other supplements for 3 months now.

Any ideas?
P.S. Regardless of the reason, I'm still happy I could help my hair at least a tiny bit.