What do you typically eat in a day?

You're going to need to slowly, key word there, work up to 2500 calories a day to gain weight. Eating 1200 will still make you lose weight. Also, since your body is finally getting food it's on this "hyper" mode and is digesting the food as fast as possible to get the nutrients. This is why you are losing weight. Personally, I believe you do need to be in a hospital. Your vitals are extremely low, I am so surprised that you're still walking and talking with that blood pressure. When I was anorexic and my blood pressure dropped to 70/50-ish I couldn't walk through a parking lot(!). You also need to be under the care of a nutritionist and a medical doctor so you gain weight in a healthy way and a steady way else your heart will suffer just as if you lose weight too fast. I know, it's ironic. I wouldn't trust my life completely on what Y!A gives. To avoid be sectioned I strongly would say to go voluntarily, that way you have more control over your treatment and what happens to you. If you are sectioned you have no control because they basically label you as unable to make rational decisions. I say, if you really want to get better, go check yourself into a hospital soon, perhaps today or tomorrow. The sooner the better so you can avoid the sectioning.