What Could Cause Tissue Like Brown Discharge?

hi sir, iam rohan.. I had sex with my gf when i had sex with her i dnt release any sperm but before she comes to me i done handjob i released my sperm..i dnt wash i had sex with her..we worried afterthat she have taken unwanted 72.with in 12hrs when she will get her periods... we met on 19th oct.. today she got brownish blood tissues it seeems so she is so tenens...her last periods came on 27th sept and ended on 31st of sept.. we are so tensed is she will get any pragency ani plz give ur valuable suggestion.. plz plzzz