I'm a bit worried with my pregnancy

I'm 5 weeks & 3 days I had no vomiting or haven't felt nauseous, I do have the minor cramps and tender Brest with lower back pain also minor and is it normal or am I to early to vomit because one of my friends had no problems with her pregnancy and her baby was born unhealthy and I was just curious like what can make a baby come out with an disability.