It's okay to sleep on your cheek after fillers, there is always asymmetry in the face. I suggest you give it a full 2-3 weeks for the swelling to settle before seeing your final result.
Midea, I suggest you see a certified injector for an in person evaluation. If it was indeed a HA filler, this could be dissolved with hyaluronidase, keep in mind swelling is common for the first 2-3 weeks
Restylane does not usually encapsulate and does not cause pain and it is probably safe, but some kind of a reaction must have taken place.
A small (3mm) punch biopsy of the nodule would leave almost no trace and would be very helpful in understanding what happened in the tender nodule...