You're not a bad Mom....it's a huge experiment raising kids. It gets harder as they get older when their decisions are more important and you have less say over what they do yet bear much of the brunt of what they experience (at least thats what if feels like).
I think it might be important not to put too much "life or death" into the decisions they make when they reach a crossroads in their life. Too much drama makes them afraid to make a mistake. He's got from now until he's 65 to figure out what he wants to do. Sometimes the most interesting adults around are the ones who don't know what they want to do when they grow up. Let him know it's ok to try and maybe fail. Let him know that whatever route he chooses he will adjust as needed. A plane going from California to New York is off course most of the time so the Pilot has to make constant adjustments along the way. It's not a straight course between point A and B. It's that way in life. Encourage him to take smart risks and to have a plan B in mind. Then let him know he has a soft place to land should he need it. What more can anyone expect you as a Mother to do?
Hang in there Ma....it will work out fine.