Light spotting & possible low hcg levels

Got my first postive hpt last Thursday I had spotted 2 before I tested and 1 day after.  I just had light spotting this morning. Called my doctor, they had me come in and take a test which showed up negative.  The doctor checked me and said I was lightly bleeding and it was probably my period. But then the nurse came back in and showed me that the test was faint but a confirmed postive. They estimated me at 5 weeks.  Going for blood work tomorrow, Monday and Wednesday to check my levels. Anyone else had this problem and had a postive result? This is very stressful. 😔