My 4 yr old bengal was spayed 31/2 yrs ago and now she is acting like she is in heat. The vet did exploratory surgery and did not find anything. Does anyone know what this could be?

You didn't give much to go on here, can you have the cat call me I need to ask her what is going on, maybe we can sort this out.

Okay so my cat is not spayed! She's acts like she's in heat one day and the next she's fine a week later it's the same... when I googled what it is like for a cat to be in heat it says its usually last a week and only happens every 3 monthes... is this normal or is my cat just weird?

It is usual for a cat to stay in heat until it is bred. Otherwise, they will be in for a week or two, then maybe out for a day or so, then back in for a week or so, and keep this up for... way too long or longer. There is no specific time frame associated with the cat's estrus cycle, except they tend to come in in the early spring, and may have more than one litter if allowed freedom to breed, as in 'living outdoors'.

The nature of the cat estrus cycle is such a nuisance that it is probably the main reason that reluctant owners get them spayed. Don't rely on Google for your cat information.