Most 7/8, 9, 10, and 11 spd chains do not have pins that can be reused, and even if a chain does have those, you don't push the pin all the way out of the side plate when you break the chain. Your chain was most likely connected with a Sram reusable link (Powerlock, I think it's called), and you were supposed to open the chain at that link and remove extra links from one of the ends, then re-connect using that link. The four pack on Amazon would probably last you through two to four chains, depending on how often you take your chain off to clean and lube. Bottom line, don't use a tool until you learn how (through being shown, reading, or watching tutorials). You need to get another Sram reusable link to put your chain back together.