HELP! A shortcut that open other shorcuts! I'm kind of desperate here!

So, a strange thing happens with me, and now, I don't have any idea how to fix it.

I was typing like I always do, using a USB keyboard, with External Keyboard Helper Pro, bought from Google Play. I usually type in Evernote.

In a moment, I'm kind press more than one key a the same time - problably a Fn, Ctrl or Alt and other. I have no ideia what I pressed! But since then, I CAN'T type anything, because  the keys open other apps! Really, if I press "e" in the keyboard, the e-mail on my tablet open, and if I press other key, other app open. I tried figure out, search in the settings from my tablet and in the settings of EKH, but I don't have any shortcuts configured!

Please, tell me this already happened with other user, and you guys know how to fix it. I'm beg!!! I really don't know what to do, and I use EKH a lot!! I'n thinking that I press some kind of shortcut that activated other shorcuts, but I don't know how to back for what its like before!
I looked at the site for the app you mentioned, External Keyboard Helper Pro, which has some tutorials. This section may help:
EKH Tutorial 5 - Application shortcuts and Text strings 

A nice feature in External Keyboard Helper is the possibility to add
Application shortcuts and Text strings to keys. In this example I will
configure Alt+G to start Gmail and Alt+M to start Maps. I will also
make it possible to quickly write http://www.apedroid.com by just
pressing Alt+A.
First I enter the Advanced settings and choose to setup some
Application shortcuts.

Perhaps that setting has what you need?