Is this characteristic of a chemical?

Hi, I’ve had very faint positives on the 7th, 8th, 9th, as well as nausea and a few other symptoms I experience in later pregnancy with my first.

I had bloods taken on Monday 9th and they came back negative. I then started bleeding the following day (two days before expected AF) with severe cramps on an off for an hour in the morning. The bleeding has continues today but no cramping, it was lighter than my usual first day but has become more red in colour today.

I took another pregnancy test today two days after the negative bloods from the doctors and there’s an even clearer faint line. Should I go back to the doctors if I still test positive in another couple of days?