Sex is always painful for me even though it's gentle. sometimes i smell like blood during sex. i have done the required std and uti test which seem ok?

I suggest you see a Gunecologist and get yourself examined and treated for your paiful sex.Most common cause of Painful sex is Vaginal Dryness.Other causes are Vaginal Infectios like yeas or Bacterial infection and STDs.And in some a condition called Vaginismus.Which is involuntary spasm of the muscles of Vaginal walls.Get checked and get treated by a Gynecologist

Painful sex is seldom due to STD and UTI have urinary symptoms so in my opinion those tests would not diagnose your problems. You need to see a Gyn to check you for vaginal reasons such as inflammation. The reason can be found and corrected and then you would be fine.