What could be causing my severe head, neck, and back pain after having a cold with high fever?

It seems like you are experiencing a complex of symptoms following a recent bout with a cold and high fever, which could be quite concerning. The severe headache, neck stiffness, and pain with eye movement raise red flags for conditions such as meningitis, which requires urgent medical evaluation. While stiffness and pain related to muscle tension can occur after a viral illness, the classic triad you describe—headache, neck stiffness, and photophobia or pain with eye movement—warrants immediate attention to rule out this possibility. Furthermore, the generalized body pain and weakness, especially with movements and sneezing, might be attributed to post-viral myalgia, where the muscles are sore and movements are painful due to the residual effects of the viral infection. However, considering the timing and combination of symptoms, it’s crucial to determine whether there are any signs of neurological involvement or systemic inflammation. You really should go to the emergency department or contact your healthcare provider as soon as possible for a comprehensive examination. They’ll likely recommend a lumbar puncture or imaging studies if meningitis or another serious condition is suspected. Please avoid strenuous activities or attempts at stretching until you’ve been evaluated, as overstretching could worsen any underlying issues. In the meantime, keep hydrated and rest, but prioritize seeking medical attention urgently.