Typing letters produces unwanted results

i am perplexed. My keyboard is not following my commands. For example,
When I type the letter a on my new Lenovo T450s, cap lock goes on. When I type the letter t I get ft.
I'm under warranty but using that service is very time consuming. I'm using OS windows 7 - if that matters. The problem began three days ago then went away that night but started today again.
Is this a keyboard malfunction or could it be something else?
Help would be gratefully appreciated.
Helenesq