Ladies, I need your input. Is this just my hormones overreacting or did my husband step over the line?

We got married 8 years ago this fall, engaged 2 years before that. His sister (my SIL) just recently became engaged, we are very happy for them! My husband came in this evening saying he just got off the phone with his sister who was talking a lot about wedding plans so he sent her our guest list and budget. I immediately told him that made me uncomfortable, I don't think anyone needs to know how we allocated money for our wedding. Plus these figures are 8-10 years old so I don't even know how helpful that is!

He apologized and told me he didn't think it would be a big deal but my stomach is in knots now thinking that my SIL has a very detailed spreadsheet of exact expenses from our wedding which I believe is none of her business.

Is it me? Or would you be mad too?