Could this lump on the lower right side of my lip 2 weeks post-Juvederm Ultra XC be a cold sore? (Photos)

I woke up this morning and noticed my lip felt swollen and sore on one side. I looked in the mirror and there’s like 3 bumps under the skin and it’s sore. I called ideal image where I had it done and they had me come in, and they said it’s a cold sore....I’ve never had one in my life, nor have I been exposed to them. Nobody in my family gets them, and my long time boyfriend has never had one. Are there any other possible causes?