If it's only at home, I would bet it's safe to say it's something you react to there. If you can smell the fumes from the cars, that is BAD. Personally I would move to a less toxic place. Dunno what else to say, eliminate as many toxic products as you can. I don't think you are crazy, very often it can be simple things around us that can cause these things. Best to try to get rid of it, before it goes any further.
Luckily I am moving to a whole new area in my state soon, this apartment is getting foreclosed on, the people we rent from haven't been paying since 3 months BEFORE we moved in. So I yes, I'm getting out of here. My biggest concern was the longer I'm exposed to whatever toxins are in this house, the more I am worried about long term affects. Just be leaving windows open for air flow and such until I move.
Look into gett a good air purifier in the interim. Eating healthy would be another suggestion, especially when exposed like you might be.