Hi Thank you for asking HCM I have gone through your query.Only 2 and half inches in vagina is the sensitive part.So you dont need a lengthy penis to satisfy your girl.You can shave your pubic hair which will give you confidence on your own size. For premature ejaculation:You should get rid off anxiety including performance anxiety and stress as those are main offenders in many.You can do squeeze and stop technique.You can stimulate your partner to maximum before getting yourself stimulated.You can deviate your thought to something nonsexual when you about to near ejaculation.You can put on a condom or condom with anesthetic which will decrease the excessive stimulation on penis and there by prevent premature ejaculation.If all these not helping then you can approach a psychiatrist for behavioral therapy and medicinal management like antidepressants.SSRIs like Paroxetine or dapoxetine are usually prescribed for this.Hope this may help you. Let me know if you have any further query.