Hi, I am new to gardening and have decided to start out with an african violet to learn. About 2 days after I bought one from the store, I attempted to repot and do "surgery" on it to separate suckers and extra crowns. After only one day after the repotting, one of the leaves' stem on the mother plant looks like it's rotting, but it doesn't look like it's connected to the crown so I don't think it's crown rot? While taking pictures, I also found a little flea-like black bug crawling on one of the baby leaves, so I'm not sure if this is a pest problem? While taking out the old soil as much as I could off the plant before repotting, I also found a tiny black centipede-like bug too. I'm not sure if I caught it before it hid in the soil though.
I have replaced the plants in half Miracle-gro AV mix and half perlite when I repotted. I have left the plants in the Florida sunroom which gets a lot of west sun, but we have thick and sheer curtains. The rest of the plant looks healthy, although the leaves are raised upwards a bit.
What do you think is wrong, and what should I do? What is the cause? A lot of my questions were answered by this forum, but I couldn't find an answer to a rotting stem/petiole. Also, what should I do with plants that has bugs in them?