Chemical pregnancy?

I had a miscarriage in March at around 7 weeks. I waited to have my period last month and then started trying again. I was meant to start my period on Sunday and decided to take a test on Friday as I had been having hot flashes and sense of smell was going crazy. The test was positive. I tested again on Saturday and got another positive. On Sunday I started getting cramps and have had fairly heavy bleeding as I would have with my period. I assumed that this was a chemical pregnancy and I only found out as I tested early. The bleeding stopped yesterday evening so I decided to retest this morning but test came back positive. Would this happen if it was a chemical pregnancy? Also had some more bleeding again today but this has stopped again now. Anyone able to offer an insight as to what may have happened?