Do you frequently find yourself ruminating on these types of irrational thoughts on a regular basis? You should probably consider consulting with a mental health expert, as this line of thinking is not normal. This isn't an HIV issue, it's a mental health issue. Therefore, I'd urge you to find a therapist in your area with whom to begin sessions to overcome this irrational thought process.
Long time to hang onto this worry. It's quite doubtful that you would have been anally raped and not realized it. Yes, you'd likely be very sore after. It's also very doubtful you have HIV. Have you never had a test in your life time? Go test one time. You are an adult and most adults should have a routine hiv test once in their life. Do it now and forget about this fear. Expect to see negative, I'm fairly certain of it.