hi im 4 weeks pregnant
after having intercourse with my partner last night i experienced some bleeding
i have taken another test 2day and its still positive
should i be worried has anyone else experienced this ?

You really should call your doctor immediately.

What colour was the blood? If it was a brownish/pinkish colour it should be okay, as its probably from the implantation.
If it was bright red I suggest contacting your doctor immediately as bright red blood indicates that its fresh, which is not a good sign.
Good luck!