Thank you for your query. Would you please clarify a few things for me? 1) Fever - how high does your temperature go? Does it come down on its own or after medications (tylenol)? Do you shiver during that time? 2)did you take any medications for the cold? If so, what? 3) The pain in your neck- does it hurt Only when you turn to the left? Is there any stiffness if you turn to your right or look at your toes (without bending your knees or leaning forward)? 4) any headache, back pain? Any vision disturbances? Fatigue is normal during an illness, it s your body s way of telling you to take it easy. Fever accentuates that tiredness as the raised temperature alters the body s metabolism to fight the infection and rejuvenate affected body tissues. Diarrhea that is self - limiting (stops quickly by itself) doesn t need any medical therapy. Sore neck maybe due improper posture or awkward position during sleep. When you have a fever or are ill , muscles tend to become more prone to sprains. I recommend adequate rest (8hrs of continuous sleep and a short nap during the day), good hydration (minimum 2.5 liters a day, drink before you get thirsty and throughout the day, fever & diarrhea can lead to dehydration, in which case you need to up your intake of water) and nutritious, easy on stomach, food. The idea is to support your body while it is fighting the infection and recovering. For your neck, (if it isn t associated with a headache, backpack, stiffness of the back and other side of the neck), applying anti-inflammatory topical preparations after a warm bath or warm compresses to the affected area twice a day may help. Do not try to force you neck to move or jerk it to see if it hurts. If you have - a fever more than 100.4 F for more than 3 days -diarrhea that continues for more than 24hrs (more than 3times a day-long smelling, with mucus or blood) - severe headache or vomiting -neck pain that or stiffness that doesn t get better after 2days -any new symptoms that worry you, See your physician right away, or go to the ER if your PCP is not available. If you stay alone, and you feel worse, have some come over till you start to feel better and recover. Hope this helps, please let us know if you have any further questions. Wish you good health.