Congratulations on one week!! That’s fantastic! For me one of the most important things that first week was learning I could resist an urge, because before that I almost never did. You’re building sober muscles. 
I think it’s pretty common to feel crappy for the first few weeks. Your body is going through a lot. Make sure you’re taking care of yourself. And if you haven’t already, check out What’s YOUR plan? It realllllly helped me understand what I was going through!