Sounds like you have damaged your engine by using the electric starter on it. You may well have had a "hydraulic lock" and then the weakest part/link will brake, i.e. the conrod or the cylinder screws....

Talk to PAW directly and they'll help you with spare parts. When the engine is repaired, then run it first without the muffler so that you can get used to how much prime and compression it needs. When primed correctly they are very user friendly and there is no need for an electric starter.