mnrcaerobat,

Try this. Fly your plane horizontally until it gets right in fornt of you and pull it straight up into a vertical attitude. TRhen take your hands off the sticks and see which way the plane pulls. If it pulls towards the bottom of the plane, then it does need down thrust. In case you don't know, the easiest way to change the thrust on your motor is to add a thin washer between the motor mount and the firewall, depending on which way you want the plane to go. But remember this, make the changes gradually. Then try the above maneuver after you make the change. You're probably not going to need a very thick washer to correct the problem.

Fly safe and have fun!!!
David