I definitely get that, especially when mixed. Too much sensory information is coming into my brain and I cannot keep up with it. it can be overwhelming. Where possible take as many breaks from the sights, sounds, smells ect that are triggering you. A quiet dark room is best and put on some noise cancelling headphones.

When I have to remain in the situation I occupy my mind with random stuff like counting trees along thats section of road, focusing on my breathe, watching the world go by from a bench or finding a retail store I can find refuge in such as an antique book store.

All this depends on where you are. The key is to take as many short breaks as possible to keep the overload down to a dull roar.