What Causes Pain And Vaginal Bleeding While Having Cyst?

i have cyst i don't know but after my cycle menstur is finished i have after 10 days litle bit bleed and sometimes i have a pain in the palces cyst..please what happen is 6 years and just one month when i was 19 years old i took birth controll and one time antibiotic and i never get treatment because i had hole in my heart when i was little but what can i use i thinking very bad every time i'm go to the doctor to did ultrasounds and say cist but now i think coming more pain and very bad i feel im full in my stomac and sore throw bothers to me i'm scared that coming from cyst this things Pleasei'm very worry I'm 24 years old i have a sex with my boyfriend i love it please I'm worry why the bleed comes from after cycle and pain sometimes worse and why the bleed coming and I'm scared same thing from 6 years agoy nothing change and scared thank you very much