After miscarriage

Hi ladies!! I had a miscarriage a little over two weeks ago not quite 3. I only bled for 3/4 days. Stopped cramping after 2/3. We’ve had sex 3 times since then. I took a pregnancy test two days ago and the second line was so faint but was there, not sure if it was still HCG levels left or what. I have been having cramps in my lower right back and lower right back for about 3 days now. What do you guys think????