Bleeding after a positive test

Can somebody help me please. I took a test on Tuesday it was positive. By Wednesday all my pregnancy symptoms disappeared. Thursday I began bleeding. Went to the hospital but the test was negative. I took a test again when I got home it was positive. Went to do blood hcg. It read 6.9. Bleeding is like a period now. I plan to repeat the beta on hcg. Had a miscarriage already last year. And this same thing happened. My tests at home were early detection. The hospital wasnt.