Took the Craftsman leaf blower apart, now what

My gas powered blower just stopped while using it. It looked like and felt like it just seazed-up, but it still cranks. I took it apart, my first ever small engine. Can see the piston, everything moves....what happened?:oops:
had that happen with my chainsaw, it seems that the wife used all my mixed gas and just put in a gallon on gas back into the gas can and what was left in the gbottle pf mixing oil, it started and ran for a bit then slowed down and felt siezed up. I let it cool down and emptied out the gas and put in proper mix and awayyyy we went