I agree with what a couple other people have mentioned. You're not alone. Almost everyone feels that way at one point in time - it's a fact of life. You don't instantly become CEO...you have to work your way up.
Also, you should increase your prices a bit. There is a reason you are getting web jobs and you need other people working for you. You are out of balance. If you can't hire anyone then ideally you would like just the right amount of work for you (meaning you lose some customers by raising the cost).
Finally, don't worry about which languages you know. If you know 5 languages, but you're not fantastic at them then you're just average anyway. Specialize in HTML, who cares? If you're the best you'll make money so keep learning.
By the way, don't buy into this whole American dream where you should go deep into debt to mortgage a new house and car. Much of the world spends much longer at home and 24 is by no means old, especially if you're saving money. Keep driving that clunker and enjoying the time with your family while you save your money.
Send me an email (in profile) if you want to talk some more.