Yes Jennifer, clearly with my dogs it got worse with age. They showed no reactions when they were young. Both of them are over 11yo now and both are hard of hearing. I wonder if it comes in at a different decibel or something. I try not to pay attention to them when it happens, my feeling is that the more attention they get the more they will indulge. I let them stay inside and they usually just want to be next to one of us. Getting them to go outside to potty is the hardest part, just as I get them out there and they actually look like they are going to go, a big blast will go off and that's it. It's actually worse with thunder because I also usually have to convince my old girl to go out in the rain as well.
My mother was of the school that if you can still walk, you aren't bleeding, and your temperature is under 103° then you are not sick. I try to be more sympathetic than she but really I don't have a lot of patience with this kind of stuff.