Is it normal afraid of relationship...what to do?

Sorry if it is long.
Hi. I'm 20 y.o guy and afraid to be in love. I think I look okay, but afraid to let a woman into my heart. I'm also a little shy. But I think biggest problem for me is my insicurities of my size. Hope you know what I mean.
Also, I do not hold much when masterbating so what if I want to make the woman I love feel good in her body. What then? I will come faster even. I was falling for a woman I know in job place but then I realize I'm no good. OK, we can be friends and even inlove. But when she see my size and that I come fast she can laugh at me. I know not all women like this but I can not shake the feeling. Pepole say real man has this has that but I'm small down there. I'm scared to be make fun of and have heartbreak. It always like this. Make me sick of it. I want to have love in my life and family of my own but scared. Ideas please? Thank you.

I work on my english. sorry if confusing.