After effects and long term effects of acid..?

well i took half a hit of acid a little over a week ago and it was my first time dropping acid. Yes i had fun and yes it was one of the best experiences iv ever had but somehow i feel changed. Everything before the trip is a huge blur like life in general before i took lsd is a blur, is that normal? Also iv always been a pretty happy person but after i dropped acid i havent been as happy and lately i just dont care. About anything or anyone and i dont know i just would like some answers as to why this happend or if it even has anything to do with me dropping acid