I accidently bough an iteam off ebay?

okay so i wanted to buy a shoe!........from ebay ...so i chose the wrong size and clicked on buy!...den i went back chose to right size and clicked on buy!...I DONT WANT TO PAY FOR BOTH ONLY FOR DA ONE I ORDED WITH THE RIGHT SIZE which is 9....da wrong one was 7.5...so i send a letter to the seller today and im hopiing her replies...incase he doesnt reply wat should i do!...i dont wanna pay for the wrong one but i do want to buy the right one, and if i dont pay for da wrong one will i be taken to courts or something cause im shitting my pants now! 10 POINTS...100 points if it were possible lol! HELP!! SOS!