So, protected sex is not a risk for HIV. You will not get HIV from non risk activity. The only ways people get HIV is from having unprotected vaginal or anal sex or sharing IV dug needles. So, your test at 27 days is going to be negative and will not change. You won't get HIV from your activity. In general, we normally say you can trust a 4th generation test at 28 days but that if someone who actually had a real risk tested at day 27, their result would likely not change. But you had no risk, you don't have HIV.