miscarriage in sept

I miscarried on September 9. I haven't had a period yet but my boobs are very tender again. I do not track ovulation so no clue what dpo I am. could I be pregnant again? when could I test?. it's been 3 weeks and 3 days since my miscarriage. TIA. Edited to say I was five weeks exactly when I miscarried it was all natural. I have had blood work done and my levels have been back at zero for over a week now. and have followed with pregnancy test to make sure they are negative..