Yes, I am highly at risk, and have been since high school or before. Take a bright stressed-out teen, add a lot of interesting factors including a group of friends who she gets to see for six weeks and then possibly never again, add school, add the expectation that she do as told and above all act "normal"...
There was really nothing "wrong" with me, I just felt horrible all the time. I wasn't near my friends; I couldn't even communicate with them regularly. I was supposed to do well in school, but I was overloaded and couldn't focus and had no motivation to even try. Books were nice, but I couldn't stay in there forever, and it was not very good when I got out.
I wasn't exactly suicidal. I didn't really want to die, I just had lost the motivation to live. Even my happy memories were painful, because I knew that I could never have that again.
Somehow, having something physical hurt, some pain I could focus on, pain I knew would end, pain I had control of, helped. I would pinch my upper arms until they looked like a flock of mosquitoes had been at me. I stopped wearing sleeveless shirts when Mama noticed and talked about the mosquitoes. Once or twice I cut the side of my hand with a pair of safety scissors. I wanted to see if I could, the first time.
Everyone was tired of hearing me tell about how much it hurt, emotionally, to be away from my friends. At first there was sympathy, but after that, I got the distinct feeling that I was supposed to have gotten over it, already, and that I had no right to still be feeling miserable over that same shit.
When my parents talked to my teachers about what to do with me this year, I sat by quietly, inert, clenching my fists so tightly my nails cut into the palms of my hands.
That was my first bad time.
Some years later, it was a very bad few weeks. Something had made me hurt very badly. I lay on the floor, unable to speak, unable to write, barely able to move. It hurt so much I don't even remember being able to cry. Instead, I bit my arms. Not hard enough to break the skin, just enough to bruise them all over. I couldn't express myself any other way, and it felt better to be able to focus on something.
It may have been in that same stretch of bad things that I cut myself and got found out. I think I had done it a few times before. I had a blade that I used for that. Never anywhere dangerous, like where there were blood vessels close to the surface of my skin -- on that same spot on the side of the back of my hand, between index finger and thumb and wrist. Cats don't scratch quite that tidily, but if you haven't seen cat scratches often enough, and know that there's a local cat, it's possible to pass it off...
My priestess-confessor dragged it out of me, the last time I cut. She was worried.
It's the same principle as going and working out past the point of pain to exhaustion when upset, only without the excuse of the workout.