So your trying to access GMAIL correct? Can you choose a different keyboard? if no, than you need to type it very slowly so you can actually watch to ensure the character you think your typing is actually the one being typed. On all the keyboards so far, if you type slow enough, it will show you the character being typed.
The SE keyboard is a bug haven of glitches. Dump it as soon as possible, and the stock android is not much better. You can get other keyboards from the market for free, so it just takes your time, but not your coin...