Gelinas there are a few things I'd like to say to you. First of all, you are 16, very young, but still old enough to know that sexual intercourse is designed to make babies. And if you don't want them, then you need to protect yourself. If this was an act that you participated in willingly, then you need to back off on blaming anyone. You both hold equal share in the responsiblity. It does not matter he if he is 'older' You and only you are responsible for what you do with your body. If you were an unwillinging partner in the sexual act, then you need to contact the authorities and file charges against him.
You can no longer be a little girl and poor me. You are soon to be a mom. Which means you have to suck it up and do what it is you have to do to raise that child properly. You don't need to answer to anyone or allow anyone to back you into a corner about the hows and whys you are pregnant. You certainly cannot undo it. (well, I guess abortion is an undo of sorts, but obviously it is not an option to you) So really, the fact that you did or didn't use protection, or did or didn't think about it is a dead issue. The pregnancy exists.
Anya had it right. You need to pursue financial help from the father. File for child support rights as soon as the child is born. Even if he is not working now, he eventually will be. And he will owe you from the day the child was awarded support. Like I said, equal responsibility. You cannot blame him, he cannot blame you. But you both share in the burdens of raising a child. I am sure some guy is going to chime in here with the "man doesn't get a choice" issue. Too bad, you play, you pay.