Should I go to the doctor or not worry about it.

I have been having Extrerme dry mouth and excessive thirst for a few weeks now, but the last few days have been terrible, I feel dehydrated, because I'm catching a cold. I have been drinking as much as possible and it doesn't help at all, just makes me have to pee way more. Then last night I started getting these weird sores on my chin, they feel like cold sores, but on my chin in a pretty large area slightly bigger than a quarter. I do get cold sores sometimes when I'm stressed, but never on my chin (is that even possible?). And my lymph nodes in my neck by the sores are swollen and very tender. I have been super stressed, my step mom died unexpectedly this week, so I expect my body to be kinda off due to stress. I'm not sure whether or not to call my doctor, I don't know if there's anything they can do about it. Should I call?