Is this a super unhealthy diet? Recovering anorexia?

I am 15 and am finally recovering after 2 years of anorexia. Lately I have been eating about 1,000 calories per day, and then exercising off 500 calories, leaving a net of about 500 calories. I know that this is not a healthy amount of calories, but I'm working on it. What I am wondering is, will my body reenter starvation mode if I continue this? Will I get malnourished, black out, or faint? How dangerous exactly is this?