now the buyer is wanting a refund and i dont the money right now and says they will get the police involved if i dont do it within 12 hours.. i tried it and it smelt fine to me.. i said in my listind if they are not happy with the purchace return it for a full refund.. what do i do?? im just a single mum trying to earn money online ;( xx

You have to honor it. I don’t know what you sold it for but you may be able to refund through Paypal and put it on a credit card. Be careful what you buy and sell.
Give him back the money and go after the website that sold it to you.
Oh, first tell him to return it you and THEN you’ll refund him. That’s standard practice.
Good luck.