What qualifies as an unacceptable side effect of medication? If I tough it out for a few more weeks, will my body adjust?

I recently had the dosage of my second medication upped a bit. On the smaller dose, I had some side effects, but nothing too major. Now my muscles are achy, I'm somewhat shaky, there's a bit of nausea, and worst of all, I've lost most interest in food. Decrease in appetite is one thing - I wouldn't complain if I ate a little less and lost a few pounds. But a lot of food has become flat out unappealing to me, which is weird. The past few days I've had to force myself to eat. I feel hungry, but I don't know what to eat. I've been doing okay as long as I stick to dairy products and fairly bland/mild foods (yogurt, cheese sandwiches, fruit cocktail, etc.), but yesterday I had some Thai fried rice for dinner. It was okay, but then I bit into a bit of onion and felt kind of nauseous. I'm hoping that this will go away after a few weeks, but I'm wondering if I can make it that long without going crazy.