28BYJ-48 Syringe Pump / Paste Extruder

I had this stepper motor in my house and I didn´t know what to do with it so I decided to make a syringe pump as I like to call it, to use with solder paste.

Since I didn't know how to get a even flow of the paste I design this little tool.

It works with a stepper motor, this motor move back and forward pushing the air out of the syringe to another syringe with to tact switches (Forward, Backward) in order to activate the motor.
Probably I'm not being clear on the explanation but, I