stomach insecurity

hi, so i’m 19 i just found out i was pregnant (i have a full time job, my family will be super supportive, and i live with a roommate so please do not comment anything on my age because i know that i am young). i have always been insecure about my body and have struggled with eating disorders when i was 15-17. i am only about 4 weeks since my lmp, so it’s very early. right now i have a little bit of a stomach that i would prefer to have gone by the time i start getting an actual bump, could i do ab exercises at the gym still? i just want to take maybe 2 inches from my stomach, i just don’t want to hurt the baby.