This is a common issue. Many photographers, especially wedding photographers, may find that they overextend themselves pretty easily. It's great to book up your summer or your whole year, with weddings. But when wedding season rolls around, you get to be very busy and the next thing you know, you are getting further and further behind on other things, like your post processing, your household chores, your family life etc.
You should try to decide just how many you think you can take, and try to stick to that....but you also need to think about the big picture and where you want to be in 3 years or 5 years etc.
As mentioned, an easy thing to do is raise your prices. That way, you can make more money for less work. If you are still getting clients, then it's a great decision. If you raise them too high, it might backfire. Actually, I've heard from many photographers that when they raised their prices, they actually got more inquires and booked more weddings. Probably because their new higher price put them into a new market segment.
A photographer I know, who is/was going through the growing pains of being too busy, just decided that he needed to expand, if he wanted to be successful, so he hired one or two people to do his post processing for him. He made a blog post about it, and it was a brutally honest post...very ballsy.
2010: an update (with an overdose of honesty) » one fine day photography
As for myself, I'm still taking every wedding & gig I can get...but it won't take many before I find that it's too many. Part of my solution to this, is taking 2nd shooting jobs. That way I can earn money shooting a wedding, but I don't have to deal with all the extra time involved.
