Chemical pregnancy

I had a chemical pregnancy at the beginning of this month the bleeding started 7th April for 4/5 days and I had a positive ovulation test on the 21st of April is a the bleeding with a chemical pregnancy same as a period where you can ovulate and get pregnant before the next period? I’ve had pregnancy symptoms and felt as though Im sure I’ve seen extremely faint positives but surely by almost 4 weeks after first day of last bleed I should have a clear positive by now?