When to take a pregnancy test?

My last period was 2 years ago. I’ve been breastfeeding my 18 month old and not sure if I’ve had my first period yet...I did an ovulation test on the 1st April which was positive. 8 days later I got some light bleeding and pain. I wasn’t sure if this was my first period or implantation bleeding? Did pregnancy test yesterday and has come back negative. But faint positive line appeared hours later. 🤔 I feel sick, have funny taste in my mouth...tired. So want to be pregnant, but wondering if I should just accept I’m not pregnant