These symptoms are not due to the injection of the product. contact your family doctor to see what is going on
I say generally not related because flu like symptoms and nightmares are not documented side affects of dermal fillers. When you say flu like symptoms are you talking about body aches , high fever, cough ? It could be that you do have the flu but the other worry would be if there is an infection from the injection. If that was the case the area would likely be red hot and tender as well.I would discuss this with the NP. Nightmares are unexplained.Finally cost that price may be under cost, and that always concerns me when a patient says the got a bargain injectable and they pay less than what it costs me to purchase the product.