check to see how tight ur battery terminals are. i kinda almost think theyre loose. ive had situations where i went to walmart, got groceries, came out and got absolutely nothing. grabbed hold of the negative terminal and it was tight but i moved it like a cm. started right up. ive also had it happen to plenty of other cars. just grab i believe an 8mm socket and take em off. double check for corrosion, put them back on and see if the problem happens again.