I Am 46 Years Old And Have Started Having Trouble

I am 46 years old and have started having trouble focusing on projects. I have also developed claustrophobia, noticeably when my fiance' sits on my lap or straddles me on a couch to give me a hug or kiss I begin to panic for air. The other day I had stuffed up sinuses and I took some Sudafed. Within a couple hours I can feel my clarity return and seemed more focused throughout the rest of the day than I had for the past year. I also didn't feel anxious and my girlfriend climbed up on my lap and we were able to talk and hug and never once did i panic. I'm thinking now that I may have a chemical unbalance and I'm not sure how to address it.