I had a heart/liver transplant on July 4, 2017. I lost almost all of my hair. Like you, I have always had plenty of hair so it was quite a shock. My hair started slowly making a comeback about 4-5 months post transplant. Now I am a little over a year out and I have a full head of hair again and ironically it's darker (my friends suspect I am dying my hair). My poor brother has been bald headed for years and I have joked with him in the past (not now) that I would trade my hair for his heart!!! Anyway, your hair will come back and maybe even better. Good luck, be patient and hang in there.