Well when you turned it over filled the combustion chamber with oil IMO. Also the gas may have leaked in also or it just ran out the cap or muffler. You need to drain the oil (make sure no gas in it) Fill it back up just below full mark but in the XXXXX on the dip stick or close to the top of the fill plug. Next you need to remove the spark plug, clean it. Spray carb. cleaner down the spark plug hole and pull the rope outside and with the ignition off. This will wash all the oil out of the comb chamber and blow it out the spark plug hole and the muffler. Now install the spark plug and start it up. It will smoke for awhile beings you still may have oil residue in the muffler. let it run for about 5 mins to warm it up and burn all the oil residue out. then recheck the oil level and your done.

if you going to turn if over drain the gas and oil. that way it won't hydro lock on you as you are experiencing now.

thanks, I'll try that, then I'll post what happens.