Waking up with a stiff neck is very common and usually resolves quickly. For relief, over-the-counter pain relievers like ibuprofen or naproxen can help reduce inflammation, while acetaminophen is effective for managing pain. Most strong muscle relaxants require a prescription, though some regions offer methocarbamol over-the-counter; you can consult a pharmacist about this option. Additionally, applying a warm compress for 15 minutes and performing gentle stretches can greatly ease the tension. If your symptoms persist for more than a few days, or if you develop numbness, tingling, or weakness in your arms, please consult a doctor. Otherwise, this should improve soon with basic self-care.