Stinky!!! Help!! 911 again

Dude, that sucks. Now you have to do an autopsy.
Take it out of the pot and look at the root ball. Rootbound? Smelly? (Yeah you have to sniff it; it's okay, sometimes I taste my runoff to see how salty it is, you won't die from smelling dirt)
Generally when you have a plant with minor root rot you can bring it back to life by re-potting into EXTRA light soil and watering lightly with some serenade mixed in, and keeping it protected form direct light. But your pot is of a shape that is hard to transplant out of, because the sides curve back in, and I bet it only has ONE drain hole- fast-growing annuals need more aeration than that.