Firefox types only numbers can't type letters

Hello,
Every time I try to type on my firefox address bar, or even the search bar it only types numbers. instead of being "www.asdfghjkl" it would type "1234567890123", it will only type in this sequence from 1 to 0 then it will go to 1 again. It's not the numlock problem and this problem only happens on my firefox, ie works fine, any other program works fine, I already tried reinstalling firefox, but it didn't do a thing. and i have no virus on my laptop at all.
I'm computer stupid, pls helpp~
thnx in advance~