If you find that it lingers, something that I find often helps (as a last resort) is just writing through it. Normally, you don't want to force it, but sometimes you just have to, because you're jammed and the only way to clear a jam is to push through it. Your post may not be the most inspired thing you've ever written, but ideally, things should come easier from there on out.
Another thing you might want to try is to find something in a genre close to what you're writing, a good movie, a good book, another roleplay, and watch/read it. When I have trouble writing for Star Wars (other sites), I find that playing Knights of the Old Republic or watching the Original Trilogy (not the prequels) really helps inspire me. When I'm writing fantasy, I find that watching (or reading) Lord of the Rings or Game of Thrones really helps inspire me.
EDIT: Further, try having it be the last thing you think about as you fall asleep. I find that I often wake up with ideas that I didn't have the night before. Your sleeping brain WORKS to solve problems while you're sleeping.