help me out, i just don't know what to do anymore...

i was born with a mild heart murmur, & i smoked something my mom didn't like a couple times (if you catch my drift.) now, all i do is worry about my my heart murmur, whether or not i made it worse, or if i caused another problem. but because of what i did, that made my mom REALLY mad (which is understandable), & now it's like i can't even talk to her about it - she doesn't want to hear anything about it. it's so upsetting & depressing. all i want is to go to my doctor just so i can get a check up & i'm too scared to tell her that because i'm scared she won't listen & it'll start problems between us again. i mean, it's to the point where because of what i did she won't let me go anywhere but school, & i can't have any friends over. i feel like it's giving me anxiety.

can anyone give me any advice? please...