Basically, every particle in my game has decided it would rather go towards the origin of the map rather than the specified control point. Help?

Did you try reloading your map?
Sometimes weird things happen...

What type of entity are you using for the control points? I always use info_targets, and enable the "always transmit to client (ignore PVS)" flag on each info_target.

This tells the game that the targets / control points are visible to the "client" part of the game, which does the particle rendering. (By default, info_targets are not sent to the client, since they are invisible.)

If the client can't find a control point when the map starts, the location for that control point falls back to the map origin.

Oh, that would probably be it. I never thought of doingthatbefore. Thanks!