There’s No I in Happy but There’s One in Stupid
Auto-correct is a feature on your phone for a reason–to avoid grammatical errors such as these. Please take the extra time to proofread your work before you post it online. It’s better to be ridiculed for taking an extra few seconds to check your spelling than it is to make silly mistakes that could have easily been avoided.
As the commentator noted, happiness definitely has an I in it. However, even the sentence itself is just so silly it makes us laugh. If you wanted to say that you were having a bad day, that’s understandable. But next time, try saying it more directly instead of trying to be clever about it.