Hi, thank you for asking healthcare magic I understand your concerns With this presentation, it is important to rule out pregnancy. You had unprotected intercourse during your fertile period and spotting (which could be in the form of brown discharge) could be seen early in pregnancy. I would suggest you do a home pregnancy test. Also an infection in the vagina known as bacterial vaginosis could also be the cause but this is often associated with an offensive odor. If you do a home pregnancy test and it is negative, then I would suggest you see a doctor and maybe do a vaginal smear. I hope that answers your query I wish you well