Numerous factors can affect the appearance of the skin under your eyes. Fluid status (dehydration or fluid overload) can alter the appearance of this area. Allergies also play a role here. If this has been an issue for only a few days, it may not be due to the filler. However, if it has been weeks, it is possible that Restylane could be at fault. I would return to your injector for an examination in this case.
restylane lasts a very long time in the undereye area and occasionally becomes more swollen with time. The good news is that it is easily dissolved with hyalronidase. Ideally you would return to your original injector. If not possible I would recommend seeing an oculoplastic specialist who deals with this problem on a regular basis. So sorry you have to deal with this problem, and best of luck.