What is going on with me?

Ok so ive been working out alot and have lost 65 pounds but now I'm always hungry, and I eat a lot now, but still seem to be losing weight. I do run seven miles everyday. Did my metabolism speed up and is that what's causing it? I've actually stopped dieting and have eased the restrictions on what I eat, but I'm still losing weight. I'm about two pounds away from being considered underweight and i dont know why. Ive also been going to the bathroom more and I feel warmer than usual.