i keep having meltdowns a person with autism and i wanna learn how to control them

i have level 1 autism, A lot of small things set me off, like loud noises being overstimulated. I bottle everything up until I get home, and when I have meltdowns i hyperventilate, cry and hit myself on my legs and head (sometimes leaving bruises). i quit drinking 3 months ago but its hard to stay sober because its the only thing that would help me stay calm, but i cant keep drinking because im on Seroquel, and other things. thankfully, I haven’t had a meltdown out in public but I don’t wanna make my family. Hate me. What do I do?