First off you are by far not inferior, and not not grown up, due to your inexperience. I promise you are not the first to be in a situation like the one you are in, or at least similar to it.
Many times men that are more in touch with their emotional side will be attracted to that in women also. It is because you can actually talk to them about things that your guy friends may not understand, or you do not feel comfortable talking about with them.
You mentioned that you cramp up when someone unexpectedly touches you, what happens when someone touches you that you knew was going to, i.e a hug or holding hands in a friendly manner, a pat on the back or leg? Does it make you uncomfortable, or does knowing in advance prevent the cramping up you talked about?
It might just be that you don't like people invading your personal space, or being taken off guard. Many people are like that, there is absolutely nothing wrong with it.
Try thinking about what happens when a male friend touches you that you know is going to, and then compare it to how you feel when a female friend touches you that you know is going to. This may help sort out some confusion for you.
You also mentioned that sex with a man is a fantasy that intrigues you, this again is normal. As people we are curious about things, it is in our nature. Perhaps you are curious as to what it would be like to have sex with a man, but since you have never felt emotionally close to one you always imagine it to be a stranger.
I can't tell you if you are gay, straight, or bi. What I can say is, you are who you are. When you are trying to sort things out, labelling yourself for other people is not that important. Don't be embarrassed that you want to figure things out, most people don't take the time to do that.
Answer that you are just you, it's the truth, and when all is said and done that is what people want to know. Your sexual orientation is a small part of who you are as a person.
There are several things I could suggest, such as you may not have met a man that you have that emotional connection with, and that is what you need. On the reverse of that you may not have met the woman you are physically attracted to and that is what you need.
The fantasies you have with men might mean that lacking an emotional connection, strangers are the easiest to think about, but as you said you could never go through with it.
I would think about the reactions your body and mind have when people you know touch you. Think about what you want in a partner. Is it possible you don't let yourself get emotionally attached to men due to fear of rejection? The same thing goes for women.
Do you have any fantasies about women?
Ask yourself the hard questions and examine how you interact with the same sex and the opposite sex. Use those answers and observations to help you decide if you are gay, straight, or bi. Until then don't worry about labels, worry about who you are instead.
Suzanne at AlterHeros