Brown discharge

Hi girls I didn't know who to ask hopefully some of you have some answers! Lately after sex with my girlfriend I have had brown discharge afterwards, once or twice it has looked like blood but mostly it is brown. I figured it was just blood but It has never been painful during or afterwards (only once). I haven't had a Pap smear yet and know I should do this but I'm scared and nervous!! Do I just go to doctor and they do Pap smear or is this a gyno thing? And does anyone have any experience with this and any suggestions?