Perfectly normal. I honestly don't think there is a normal with clowns because they will do anything under the sun.
They way I would read it is, Your clowns are paired, the female is in the nem stating her dominance, but has put her partner in timeout in the corner of the tank. Give them time, she will eventually let him in.
I've actually got a small pair od Picassos that are doing the exact same thing. Although they are small enough that you can't tell the sex, I'm guessing the female is in the nem, with the male being banished to the PVC fittings in their growout tank.
Scott