I agree that it sounds like you've flooded the engine.

When I start my engine, I only prime it by plugging the carb while hand-flipping the prop 2 or 3 times with the carb at half throttle before connecting the glow plug clip. The electric starter will draw fuel very easily.

To clear the engine when flooding is suspected, disconnect the fuel supply, remove the glow plug (cover with paper towel if available) and spin it for a second or two (it doesn't take much). Then re-insert the glow plug, reconnect the fuel supply and start over with less priming.

Another easy priming method - place a finger over the muffler's exhaust port for a split second while cranking the engine with the starter. This briefly increases the pressure feed to the fuel tank, resulting in a rush of fuel.