I think I broke my laptop's keyboard..?

Okay heres the deal, I currently have a Acer aspire 5742z-4512 and I decided to disassemble it so i could clear some of the dust buildup that was in the fan so everything went fairly well while disassembling it until I got back to putting the Acer Keyboard back on which was kind of difficult, i managed to get it back on but the "Esc" was a casualty and popped off, to make things worse, the lil joint thing that goes on the key broke so basically i said f the key and continued putting my laptop back together, once everything was back in place and looked good, i realize that my Function key isnt working nor is the entire top row of buttons (Esc-Del) but odd enough my home/pg up/pg down/and end work fine. Someone help, im pretty sure i didnt mess anything up, is it a system issue that i can fix or should i get a replacement keyboard, i planned on doing so anyway but i just wanted to see if that was the only option in fixing this issue. Please help if you can. Appreciate it.