Necrosis? After Juvederm injection to lips, they're white & purple. Everything around my lips & cheeks is puple & hurts! (Photo)

Yes, no question, this is an extreme emergency that needs immediate attention. You need hyaluronidase, aspirin, nitropaste, and probably hyperbaric oxygen. When you get a reticular vascular pattern outside of the area treated with discomfort, it is no doubt vascular occlusion. Please see someone soon. Don't wait. 100's of units of Hylenex are needed but best outcomes are when this is treated within minutes, not days. I don't think you've been diagnosed correctly. I don't think they lied, but just inexperiened with this problem. I would go to a different office for follow up. 

Thank you for your question.  I cannot render an opinion without examining you myself in person, but the serial photos you have sent are certainly suggestive of a combination of filler swelling and perhaps some arterial tamponade/blockage as well.  The net like appearance of your right cheek and upper lip may point to an artery that isn't feeding the skin properly.  I would urge you to see another physician locally and quickly to get this assessed.