Will my hairs grow back ?

I experienced hair loss at my temples due to severe vitamin deficiencies. My hair fall has now reduced to around 10–15 hairs per shampoo. However, I keep wondering whether the hair lost because of these deficiencies can grow back and return to normal.

I also notice many baby hairs on both sides. Some people say baby hairs are normal, while others say they indicate hair loss or new regrowth; I’m not sure which is true. Since I’ve started taking better care of myself, my hair quality has improved, but I really want the hair at my temples to come back, as my forehead looks bigger now. The deficiencies were major vitamin D and minor vitamin B12.