I missed my period last month (dec) i took 2hpt both neg, now i am late for my jan period.on my ovulation day i had a spot of blood could be pregnant?

Probably not: It sounds like you are not ovulating regularly. If you are skipping periods you may have a hormonal imbalance or pcos. You should see a physician to be evaluated with blood tests and possibly a sonogram to see why you are missing your periods. If you would like to get pregnant you may need Clomid (clomiphene) to help with ovulation.