I have pcos. i took clomid 50mg+letrozole 2.5mg after 2 failed cycles on 2.5mg letrozole. cycle day 13 u/s showed a big follicle on my right ovary. doc said i o'd-day 21 level=13. could i be pregnant if i'm on day 32 with negative pt and no period?

If ovulation was documented on "day 21", a pregnancy test on "day 32" would be negative even if fertilization occurred. If HSG shows open tubes, and semen analysis is normal, pregnancy is possible. Obtain a serum HCG test in 7-10 days to be certain about pregnancy. Ask about a HSG (hysterosalpingogram) to make sure your tubes are open, to maximize chance of fertility.

IF you are saying the day 21 progesterone was 13, this indicates ovulation likely occurred on cycle day 14, more or less. The pregnancy test would be accurate either way, positive or negative, if this is true. So likely not pregnant.