No more kids

So my husband is going to get a vasectomy on the 11th. I'm very back and forth on that idea but he's very dead set on getting one.we have three kids together. we have 11 year old and 9 year old and a 1 year old. I'm going to be 35 in a few months and my doctor already told me that I need to start thinking about not having anymore kids because I'm getting to that age where anything can happen. I'm having a hard time dealing with that part of my life is coming to a end. Am I being overly dramatic? I'm so thankful for my kids that I have because I know so many women can't have babies. I just feel so confused!