A work experience

So I started working Monday... and had to quit the very next day. I am ashamed to say that. The job was physically demanding...one I had done before, and one I thought I could do again. Sadly, I could not. I hurt sooooo bad I could barely move around. I was in bed most of the day Tuesday and didn't really get up till I had to go get my son from the afterschool program. Then we drove around for an hour or so afterwards because I didn't want to get out of the car. This was like a slap in the face that I really am fat, that I really am weaker than I used to be. Did this experience strengthen me? I KNOW I want to lose weight. I KNOW I want to gain more muscle. But for some reason I keep finding myself stuffing my face with "comfort" foods. Cookies, cakes, doughnuts, pastas, breads, etc. I am drinking protein drinks to help rebuild my muscles...but that seems a small victory and overall void when compared to the rest of the junk I have been munching down on. So where do I go from here? I'm not sure where I will go with this...I KNOW I want a slimmer, healthier me...but I feel so beat down and ashamed.