How to get rid of this farting problem?

Ok,I fart a lot in school but when I get home I don't. When I get home it like magically goes away but in homeroom it comes back and I don't even eat breakfast!! We are having testing this week and some of next week and I have to sit in front of this guy. Farting is distracting me from learning and embaring me!! I can feel but I can't smell it when I let it ease it's self out like when I'm not pushing to try to fart. I told my mom and she told me to take a laxative I did and it hasn't really helped. It's been going since the 4th grade I haven't told my doctor bcuz it's embarring!! I just wish I could go to school and be a "regular kid" I know everyone farts but not ALL the time. Helpp plzz I have testing tomorrow!!