Did the compression blow your thumb off the no 1 spark plug hole? If not, it might not have been the compression stroke. Have someone crank it over a time or two so you can make sure. Also make sure the plugs are firing across the gap, not just to from the plug to ground. Its pretty easy to foul the plugs while trying to get something running, I have replaced many sets of plugs that were fouled so bad the engine wouldn't start.
