My (ex) Gf And I Had Sex Towards The End

My (ex) gf and I had sex towards the end of her period on 12/25. She had a bartholin abscess about a week after. She recently had it drained. However, she has not had her period since. She usually gets them every 23-25 days. Do the bartholin cysts delay periods? *she had stopped taking birth control at the time.*