Very faint positive

So my boyfriend and I first started having unprotected sex 2 weeks ago, I took a test yesterday and it was a very faint positive line that came up within the 3 minutes...I rang my doctor and she said that's still a positive but I'm still so unsure and scared that it's just a chemical pregnancy, so scared in fact that I havent taken another test.. I miscarried mid august 2017 so that's why I'm so scared, anyone else have this feeling?? I'm having symptoms like tender breasts, nipple changing colour, bloating etc but I'm wanting some reassurance please and thank you!