Re: Check out
This is one of the times when the US version of English uses the simple past (or present perfect - both are fine) where our British friends use present perfect.
It's actually not that uncommon when someone knows I'm at the grocery store to get a call. "Hey Mom, are you still at the store?" "Well, yeah, but I finished shopping and I'm line to pay/and the cashier is ringing me up now -- what do you need?"
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.