I also train on the C152, if you have pressure pulling stick where you have it, trim down, if you push the weel forward trim the wheel up.
Just trim the force away, most of the time it will be very very gentle, only a few centimeters if you ask me.
Basics: first put the airplane where you wan't to have it THEN trim, if you need to lower the nose a little, DO NOT trim a little down, push the stick a little forward and trim
Don't worry at all, you will be into the art of trimming in no time