As our members are telling you, no one here will know if you were penetrated or not. Only you know and since you don't, the only option is for you to take a test. Any test you take now would be conclusive as our members state. We wish you the best.
** thread closed **
This happened 4 YEARS ago? As AnxiousNoMore has told you, take ANY test now for a conclusive result. You can purchase a quality home test kit and get your answer without having to see your doctor, since that is apparently an issue for you. Have you not had any exposures since this one 4 years ago? If you have, depending on when they happened, our advice to you could change.
The thing is his penis get into my anus a little as what I said before(just the tip of his penis),Is this the actual penetration or not
If there was no penetration, there was no risk and you stated you have experience and know there was no feeling of penetration.
However, since this has been bothering you for 4 years, and you know you had no risk, the simplest resolution would be to take any test, collect your negative result and put this behind you. There is no reason to fear a test if you are negative, but you state you are afraid so talk it over with your doctor before you test so he can explain the value in not having to worry about this anymore.