I Am 3 Weeks Post- First Metacarpal Osteotomy. Had No

I am 3 weeks post- first metacarpal osteotomy. Had no pain during first 2 weeks in first cast. After 13 days, I got stitches out of my thumb and new waterproof cast. This was 7 days ago. About 2 days ago I have some aching pain at base of thumb where incision is, like raw wound being rubbed in cast. The hand inside my cast feels hot, but my fingers which stick out are cool, not swollen, and I am afebrile. Could I have infection, rejection of pin/wire, or is this pain normal?