No, your penis size has no relevancy to the pleasure of you or your partner.
Quote:
At the 'advanced excitement' stage of sex, part of the vagina expands so much that you may think he's lost his erection. He will, of course, deny this - and he's right.
When exteremly aroused, some women don't even feel the penis inside of them. This doesn't innterupt their pleasure state because although there are nerves inside the vagina, the majority of sexual pleasure comes from Gspot and clittoral stimulation - neither of which you need a big penis for. You just need good positioning and proper knowledge/education.
Sexual stimulation is lumped into several different catagories: manual, oral, penile, and mental.
Those are your tools to satisfy your partner. You're penis it isn't going to be the only thing you are using. And when you ARE using it, use it properly and the 4(or 8 ) inches won't matter. Your sexual competency and performance will come from all of these, not just one. If your penis size is lacking, make up for it in one of the other three. You are still arousing and stimulating the same amount - just in different forums.
Outside of that, it actually all comes down to your mindset. If you sincerely enjoy the person you are with, then you will both make efforts to reach orgasm with and for eachother. Because both of you CARE that the other person gets off. If you care about anothers pleasure, you are more likely to apply yourself and do whatever it takes.
So stop worrying about your penis size, and start ensuring you are a well rounded sexual partner.