sounds like it may be having a seizure. Yes this would be bad see a vet.
only bad things. You will kill it if you squeeze it too hard or too often. Be nice to it otherwise give it to someone who cares.
no
Just let him rest for about a week or two then he or she will be as playful as ever!
Do not be alarmed. This is very common. Your little hamster is showing affection for you! That means that your hamster loves you! Or it can mean something else. If you groom your hamster, the hamster would want to groom you back to show his/her appreciation. It's the same with rabbits.
Clicks, squeaks, shakes, leaking lubricant.
depends if it is a hamster that is fat or a big bone hamster depends really
You should never try to punish your hamster it is not necessary as they are not smart enough to learn or know that they are doing something bad. If they "do something bad" while you are holding it you could just put it back in his cage. Do not try to do anything like remove his food, toys, or water.
NO
Sometimes it could be they are warning others of danger. They do make alot of noise when there is no danger.
is eating dirt bad for humans? yes
It is bad for a hamster to not have a wheel. Hamsters need their exercise or else they can die.
As an owner of a guinea pig, i say yes, a hamster can be bad for asthma because: -The litter in the cage gives off dust, which can become an irritant -The hamster sheds, and the hair can irritate the throat