symptoms: pain in knees, left elbow and forearm; gums are swollen and tender, canker sores, right pinky toe is heavy with dull ache, abdomen pain, lower back pain, red welts all over - 20 or more. Came on suddenly. Am I having an allergic reaction? bug bite? what else could it be? I need help. Went to hospital emergency and they could not tell me what is going on and sent me home. Did take blood test which came back normal.