Welcome to HCM
We understnd your concerns
You have 4.3 inch penis and you are worried about it?Please do understand that size of the penis never matters in sexual intercourse. You are anxious and apprehensive about your performance. This condition more psychological than physical.
You can try imagery method. Daily imagine having great sex with any girl you prefer. Don't masturbate. Just imagine for 2 minutes. Feel that everything is going well in that intercourse. Do this for a week or so.
If problem persists, consult a psychologist
I can help you if you desire so.