Other than waiting a few days, is there a way to increase my semen volume? And thickness?

Drink fluids. Making sure one is well-hydrated may increase semen volume.
Semen volume. I am not sure why you care about the semen volume and thickness because those characteristics have nothing to do with function or quality of sperm. If you are worried about fertility then a semen analysis is more important to give you information. Perhaps if we knew why this bothers you we could give better advice.