Nervous about 2nd child at 35?

I recently found out that my husband and I are expecting our second child. This was planned, but now that it has happened, I am not happy. I will be 35 when the baby is born so all of a sudden I feel extremely old to be doing this. I also have chronic hypertension which adds to the nervousness that I am having. Now I almost feel embarred for being pregnant. Has anyone been through something similar? Words of advice to get past this?