What Causes Burning Sensation And Numbness In Fingertips?

My 12 year old daughter is complaining that the tips of her fingers and her feet burn and are possibly numb. she has pain when touching the tips of her fingers or tries to bend. She also complains that its annoying when she walks. This has been going on for just over 2 days. She woke up this morning with a slight slight rash on her hands and lower arm. Should I be concerned?