Spotting after sexual intercourse// TMI!!!

Whenever i end my period and i have sexual intercourse like 2 days or 3 days after i seem to start spotting and like the blood is bright period red, it worries me because now i ended my period on monday and had sexual intercourse on Wednesday and bleed and bleed on friday 😐 and stopped saturday throughtout the whole day and now i had sex again and i strated bleeding once again, any suggestions on what it might be or how to avoid it???