many odd habits, I need some help

I've developed so many odd habits over the years that I can't seem to control. Most go away for a while and can be gone for quite some time before showing up again for no apparent reason. They've been around for as long as I can remember and I've never mentioned them to anybody since quite a few of them are pretty strange. I'm hoping a doctor will be able to give me some idea what my problem is and how I can resolve these issues. I was diagnosed with selective mutisim as a kid which to this day has never been completely cured, so I don't know if that has anything to do with any of my habits, but I felt I should mention it anyway. I'll just list them below, so you can get an idea of what I have.

- I'm unable to write with a pencil for very long because I apply a force when writing that causes the pencil lead to break. Because of this I always have to write with a pen, but even with a pen you can see bold ink marks on the letters I write from applying so much pressure.

- I gently bang objects on the corner of things. For example with my remote control I bang it on my chair and with my computer mouse I bang it on the corner of my keyboard, or PC monitor.

- I touch hot objects even though I'm aware that they can burn me. For example whenever I'm brushing my teeth I'll touch the curling iron, when I'm in my room I touch the top of my light bulb, and when I'm making food I touch the stove top. All of these things I do whether the thing is on, or off. I don't do it because I enjoy pain, or wish to cause myself harm. I can't understand why I do this. It's just something I feel I have to do.

- I make this sound sometimes that just happens on and off. Some days it doesn't happen at all while other days I just can't seem to get it to stop.

- I wouldn't really call this a habit (it probably has to do with my selective mutisim). Anyway it's very hard for me to make eye contact with someone for more than a few seconds. This makes really any social interaction difficult for me.

These are really just the top ones. I have so many things wrong with me that I don't feel comfortable mentioning anywhere. I'm hoping I can get help some help with the problems I mentioned and maybe someone has an idea what's wrong with me.