One work week down

Going back to work has been awesome and terrible. I was so happy to see/meet my kids but haven't been in this much pain since right after surgery. My ankle hurts and my knee constantly aches. At night I am exhausted but am back to not sleeping well because of my knee hurting every time I move. It's no good. I love my job but unfortunately it is one where I run around a lot and pick up kids and very rarely sit down....and when I do it is in a mini chair and I have to get up immediately. I am feeling torn- I know I went back to work too early, but will I ever feel like I am ready to be back? The only way to know if my knee was ready was to go back and my answer is not what I wanted. Boo. All I want to do this weekend is stay in bed and ice and feel sorry for myself.