I’ve been having some major issues with my mouse for the last two months or so - double clicks being registered when I perform a single click - and despite cleaning it out several times and changing over to another USB port, the problem has gotten worse and worse, to the point that any precision clicking, ie tracing, is incredibly irritating. Don’t expect any more Negima traces from me until I’ve had a chance to go buy a new mouse, which probably won’t be for at least another few days. I was going to go today but everywhere was closed. 
It also won’t help that I recently noticed TRSI selling all of Cardcaptor Sakura for $80 and decided to pick it up. I’ve had a few random DVDs from the series as well as both movies for years now, but kept putting off picking them up until now.
UPDATE: New Mouse GET
wow thats an amazing price O_o
There’s some setting in Windows that can cause a mouse to do that. Can’t remember exactly where it was at, but I had the same problem about a year ago, and was able to correct it by playing in the control panel for a bit.
That setting is a permanent one. This one is random and periodic, which is why I believe that it’s the mouse itself rather than a software conflict. I’ve seen similar things happen with USB keyboards, with double key repetition from a single stroke, but that usually can be fixed by simply changing the port around.
Also this mouse is now 7 years old, so it’s not unlikely that it’s on its last legs.