C172 Student Pilot reported selecting the improper flap and carburetor settings resulted in a runway excursion.

Narrative

This was my first solo flight and my original intention was to do three full-stop taxi-backs. I landed on [Runway] XXR and exited the runway via [Taxiway] XX and then taxied back to Runway XXR via [Taxiway] XY. I did not perform the after-landing checklist and the carburetor heat was left on and flaps were left at 30 degrees. ATC provided clearance to takeoff on [Runway] XXR and fly straight out. I started to take off with carb heat on and flaps at 30 degrees and did not note this error until I observed that the plane was not accelerating normally and was beginning to lift off the ground around 40 kt. when rotate speed is 55 kt. I put the throttle to idle but was not able to maintain directional control and the aircraft veered off of the runway into the grass between Runway XXR and XXL. I was able to brake the plane to a full stop in the grass and then taxied back onto Runway XXR and requested that the flight be terminated and taxi back to parking. This experience emphasized the importance of the after-landing checklist so that all procedures are followed to ensure safety.