Have you had your hearing checked lately? The fact that you have trouble hearing people because of background noise might mean you have some hearing loss. That's one of the symptoms I had when my hearing was dropping off. When I'm in the grocery store, the music and the air conditioning fans, etc. make it so that I can't understand the cashier. It seems the background noise is far louder than the person speaking to me.
Loud noises bother me, too. Things that don't bother others can make me jump! If you know you will be in a noisy area, perhaps use earplugs for comfort.
Sherrine