anxiety before surgeries (any surgery) is pretty common...I always freak out before any surgery I've had. And they've all gone off without a hitch.
first, morbidity rates on weight loss surgeries are really low. It's 0.3% for bypass, even lower for sleeve (not sure the exact percentage for sleeve since I had the bypass - but sleeve is lower). So there's a 99.7% chance (or greater) that you're NOT going to die - and those are excellent odds! Even better than hip replacement surgeries, which people get all the time. Weight loss surgeries have improved tremendousy over the years and they're no longer the scary, risky things they used to be. They've really become pretty routine at this point.
I don't think most surgeons use catheters for weight loss surgeries, because unless you have other issues going on in there that they have to deal with, the surgeries are short. My bypass took a little over an hour - sleeve surgeries are typically even shorter. I DID have a catheter for two of my plastic surgeries, but then I was under for over four hours with those. The catheter wasn't any big deal - but no, most of us don't have one for weight loss surgery.
the surgery won't fail as long as you follow the rules and guidelines. It'll work like a charm. But you do need to get the binge eating under control, because that could sabotage your efforts. They'll probably have you meet with a psychologist prior to surgery (that's very common...), but you may want to continue meeting with a therapist even after that because the binge eating WILL hinder your results if you can't get on top of it. Many of us have worked with therapists and found it very helpful.
I can't speak to the being too young part, since I had surgery at age 55 - but like others, my only regret is that I didn't have it sooner.