If i had unprotected sex in oct would hiv result show up on test if taken dec 15 14?

No: Our latest tests will be positive at four weeks. You have seven days to wait. If you test negative you should have a further test at three months just to be absolutely on the safe side. I have to reinforce what you already know, namely that you should always practice safe sex until you are in a stable and settled relationship.

Yes: The fourth-generation HIV tests are very sensitive. If the test was negative, you don't have HIV. If you had a very high-risk exposure such as sexual contact with a known HIV positive person, you should repeat the test. Otherwise, its not necessary. Best wishes!