Is this a dedicated receptacle? If not, and you check current at the panel, you will also be measuring other loads. If you have zero current when the strip is unplugged, then you can probably assume that nothing else on the circuit is drawing current.
I agree with resqcapt19. If you don't even know how to use an amp meter, you should not be opening a breaker panel up. However, you can safely use a line splitter and some versions are quite inexpensive. Check Sears, as that is where I purchased mine a number of years ago.
