Brief Answer: I am concerned.. Detailed Answer: Hi, At 13 years, various lumps under the armpit and jaw which seems to enlarged lymph node; the rashes, myalgia (muscle aches) and low grade fever are suggestive of an ongoing infection. It will require a detailed clinical examination and battery of tests to isolate the causative infective organism. Since the symptoms are ongoing, I would be concerned; therefore insist on early evaluation. I recommend that you visit your primary care physician or your pediatrician at the earliest. Hope this helps. Let me know if you need clarifications. Regards

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