If you get any air trapped in your ears, you can get a squeeze on the outside of your eardrum. It feels like you aren't equalizing even though you are. All you need to do is burp the hood as soon as you get under the surface to let the water on your ears. After that, no problems.
I don't see how that would cause your ears to explode outward. My ears don't always flood, hood or no hood and I've never felt any discomfort either way, unless the water entering is extremely cold. Any discomfort is not a result of a squeeze though, but rather a sharp shock inside my ear from the cold which goes away as it warms up.