You missed the rest of the plunger in the tube plus the plunger is kinda short considering how much liquid you put in there but getting proportions right on something humorously oversized is always difficult.
Besides that great picture as always. I'm ready for my lucozade injection derpy, directly in my mouth please.
also the i think the perspective is a bit off between the part of the plunger shes holding and the disk inside and the rest of the syringe that it would be connected to. right now it gives the appearance that the plunger is bent back away from the viewer quite a bit while the rest of the syringe is pointed down and slightly away from the viewer in the opposite direction.
other then that i think it looks very good. and derpy is cute as always :3