If a person tries her best to confess everything but after confession worries that something has not been confessed, and remembers something that may not have been confessed or not confessed properly… does she need to confess this remembered thing at the next confession, or just forget about it? Is it okay to just go ahead and receive Communion?
It is definitely OK to just go ahead and receive Communion.
Ordinarily you should mention it if it was a mortal sin at your next confession but you can still go to Commmunion in the mean time. But in your case if you suffer from scrupulosity, my understanding is that you wouldn’t need to mention it at your next confession. But you can if you want to.