Stress could be the origin of your problems.
For me, too, the symptoms you described are familiar. Generally if not accompanied by a fever, I will file the problems in my MS folder. Before my fingers get really sensitive, as you described, I have signs I quickly notice. Plastic shopping bags or trash bags and certain paper stock (such as some newspapers) will "bother" me. That is, I do not like the feeling or the sensation. I take care not to touch them and I try to relax. The sensation can linger for weeks. The only way to know if it is getting better is to try it.
The sore muscles, yes, I, too, understand that pain. Physical strain/ over-work/ over-exercise....there are a multitude of possible culprits- including stress. The temperature change is one trigger I cannot control. I can understand your problem.
Though your job as Mom is tough, it is important that you get adequate sleep. If your "sleep savings account" is in the red, a single weekend will not replenish you. Lack of sleep affects many people with MS. A VA study here in the states noted the high percentage of sleep problems associated with MS patients. Though it may be difficult, try to find a way to get more rest. Yes, I realize a sick child means some sacrifice, but if you are not healthy, how will you be able to provide quality care for your child?
Rest assured that you are not alone with your dilemma. Having a sick child is quite stressful. I can well empathize with your situation. You are still in my prayers.
flu like symptoms and sharp stabbing sensations? 
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