I'm 16 and i smoke lotsa weed and sometimes i dont realize i said somethin?

for example, today i was talkin to my aunt...she got a new hairdo and she's extremely overweight...like 350 lbs......so i complimented her "nice hairdo, aunt melanie!" then i muttered....."but you're still REALLY fat..." and i didnt even realize i said it. she was all like "...did you just call me fat?" lol and i was like...WHAT? no!!! i said it in my damn head! wtf! LOL HELP!!!!!!!!