I have a male who seems to be very reluctant to lock.

I noticed a lot of tail wagging going on the last two times that I paired them. Last night I heard what sounded like quite a lot of activity going on in their tank so I looked in, and was surprised to see that it was the male.

He seems to get very highly active during the first 45 or so minutes that he's exposed to the female. He moves in a quick, jerky way and darts around the tank, wagging and lifting his tail.

Is this because he's interested in the female, or is he really stressed out? Is it a good or a bad sign? Right now he is curled up in a small ball, as far away from the female as he can get.