Concerned about being pregnant after 40.

Amazing

I may be pregnant and I'm about to turn 43. Although, this is my 3rd pregnancy I haven't done this in 18 years..my kids are older in college. My SO is 9 years younger than me and wants to have his own child with me. I'm not sure what type of prenatal help, advice, doctor etc. I should seek. This was all unplanned And I'm also very much concerned of not having a healthy baby. I have so many worries. Any advice?