Super irregular periods

So i am a 19 soon to be 20 year old girl who had always had irregular periods. Like seriously my periods used to come like every 2 months then it’d be every month then be spaced back out to like 3 months and so on but now for some reason i don’t even know i haven’t had another period since the first week of June and it’s the first week of December! Like that’s a whole 6 months without a period, now that’s great and all that i don’t have to deal with the period pains and stuff but I’m starting to really freak out. I’m not sexually active, I’ve only had sex once and that was almost 2 weeks ago so i thought it might make my period come but it still didn’t. And i haven’t changed anything in my lifestyle, if anything I’ve gotten healthier since i started going to the gym a while back too. Now i am a college student so i am always super stressed out but I don’t think that could cause 6 months without a period, right?

I sometimes have gotten the period symptoms during this 6 months but no bleeding. Idk what to do and I’m not sure what could be wrong. Anyone have some advice or tips to kickstart my period again?