key stuck on keyoard - guess the letter not working!

I'm on a laptop and when it starts up it keeps beeping fast (been able to use the b using spell check then copy and pasting it)

When it finishes starting up and i load any application i.e work firefox, as soon as i click in a text box the letter b keeps on typing and wont stop. If i press another key it stops, however if i then press the b key nothing happens.

I've taken the key out of the keyboard and blown air. Also made sure nothing was under it, however it made no difference.

Oh and if i press all my keys like below sometimes the letter b does work but not often. Any help would be much appreciated. (This has been extremely annoying typing this having to copy and past the letter i require)

example:
a\wzgbvhj,nhgvsdcgghj,ngfdscedrtgv cdgvdcsaergvsagbylp;lkgvfdgvgfvgngvn nhnjmnvghngvnv

thanks