I agree with Mike D; an intro to Scuba is just that - an introduction. There are a lot of different skills that are needed to Scuba dive. These skills are difficult to master in a one hour session. Buoyancy is a skill that takes newly certified divers a few dives to master and comes with practice. The problem with your ears is also something that your body needs to get used to; after a few sessions in the pool your ears usually adjust to the pressure and you are able to equalize more easily.
If you are still unsure about enrolling in a full certification course you could try another pool introduction (possibly private) to see if you will adjust to being underwater.
Don't give up!
If you are still unsure about enrolling in a full certification course you could try another pool introduction (possibly private) to see if you will adjust to being underwater.
Don't give up!