Hi Thank you for asking HCM I have gone through your query.Regarding size of penis:only 2 and half inches in vagina is sensitive part.So a big sized penis is not needed to satisfy a women.You can shave your pubic hair which will give you confidence about your own size.If it is very small and difficult for intercourse then you can approach an Urologist for enhancement surgery. Regarding Premature ejaculation:You should get rid of performance anxiety and stress.You can practice 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 drugs.Hope this may help you. Let me know if you have any further query.