pls help :( !!

so today i noticed these little tissue like pieces in my discharge (see picture) and i dont know what it is ?? ive never had this happen before

i was supposed to get my period on june 4th, but its hella late and has not started.

i got my period in may & because of quarantine, havent had sex since like march LOL .

however , i had unprotected sex on june 11th , he pulled out. i know for a fact that he is sti/std free, as am i .

and now im noticing these little tissue like pieces???? & my period still hasnt started & im pretty sure all this added anxiety is delaying it even more but a sis is freakin out , what is this tissue????