A wise word of advice; don't try to find things wrong with yourself. It only serves to make you unhappy. You might be a little paranoid, and I don't want to invalidate that feeling, but it could be a lot worse. Honestly, there are people like myself who wish for your (relatively) healthy mind. It could be much, much worse than some slightly uncomfortable feelings of paranoia. That's all they are; slightly uncomfortable feelings. From your description, we can completely eliminate the possibility of chemical imbalances (which suck, in case you were wondering, good on you for not having any)
Just focus on positive things. That's what I've found helps. If there's something you don't like about your life, with enough effort, you can surpass that which holds you back and change that which upsets you. I wouldn't go to a doctor if I was in your shoes. Doctors are mostly a waste of time. Most problems can be fixed by doing a few simple things.
The first is being organized. For me, this is the hard one, but it saves a lot of stress when you can find anything you might need in its place. Stress, as you probably know, only increases the severity of various ailments.
The second is exercise. It's simple enough. Just get off your ass and run a mile or so a day, lift some weights, do some other form of cardio, boom, less than an hour and you'll feel amazing when you're done.
The third is eating properly. A stuffty diet can cause all sorts of deficiencies, none of which are good for mental health. Just eat balanced meals, try to cut down on junk food, my tip is eat stuff that doesn't come in a package or box, like fruits or vegetables.
To tie into the above tip, learn how to cook. It's fun to do and generally, unless you're frying twinkies in lard in your kitchen, the food you cook will have fresh ingredients and be generally pretty good for you, compared to stuff you'd get at a store pre made/frozen.
Hope some of this helps, It's really helped me.
