mysterious red bumps

About a week ago i woke up with about 10 swollen red bumps on each of my legs. there sizes vary and on my left leg i have one on each side of my ankle, which is very swollen and it's making it difficult for me to walk. the bumps don't itch but they hurt. They are very sore. In the past i've had cyste and acne but nothing like this. they don't seem to be going away or getting better. They feel like a knot under my skin. I'm so scared and worried what is wrong with me?