I have PCOS but think I may be pregnant.Please help me!?

I am 20 and my husband is 24 years old.I was diagnosed with PCOS when I was 16.Had cycts on ovaries,elevated testosterone levels,and weight gain.I have always had regular periods with the exception of a couple being 2 or 3 days late.I was put on metformin which I can not take because it drops my sugar levels and even though I have PCOS Im not insulin resistant,my sugar test levels are normal(my old doctor who put me on metformin was just going on my sonogram results and not my bloodwork).Also Im on spiraldactone to help with my hormone embalance.I have been TTC for 2 years 1 month now with no luck.Recently my last period was on JULY 26 and Im about 11 days away from my next one with really sore which I know is a sign of pms but I have never had it before only cramps in my ovaries.I have clear skin but woke up this morning and Im covered in acne real bad. Could this be a sign of ovulation or something this far from my period?I have a period so why cant I get pregnant?