Having a relapse with my eating disorder?

At thirteen I was diagnosed with anorexia. I got help and gained back the weight. I stayed at an average weight for two years. But now I'm slipping into old habits. I've eaten twice since Tuesday and lost three pounds since Friday, another pound since yesterday.I'm terrified to gain weight. I workout multiple times a day. I have such low self esteem hence the past with anorexia. Am I having a relapse? I really need to know.