bleeding after sex

Everytime my partner and I have sex I bleed for atleast 5-7 days afterwards. It's like a full blown period. I can have sex one week bleed for 5-7 days. Finish bleeding then have sex a day or two later and it's starts all over again. And on top of that I'll still get my normal period. Does anyone else have this issue ? Ive started the process to find out what's going on but I want to know if anyone else has this problem.