子に痴話!
Welcome! So, uh. Lesson number one: be careful when using an IME, because the first suggested kanji is often not the one you want to use. What you just wrote was “sweet nothings to a child”. =P こんにちは is usually written in hiragana anyway.
Which leads us to lesson two: it’s spelt こんにちは. If you’re using romaji-based entry, you’ve gotta be careful when ん appears next to a な-line or あ-line character – if you type “konnichi” you’re going to get こんいち. You gotta write “kon’nichi” or “konnnichi” (yes, that’s three Ns). Think what you wrote was “konichi” anyway. And it’s は rather than わ, though you’ll learn why in a bit.
But yeah, enjoy your stay. =)