I'm losing my mind with the child ? The last week she seems like some…

I'm losing my mind with the child ? The last week she seems like someone else, nervous, capricious, sleeps poorly, eats not so well... teeth are hurting, I don't know if it's related to her psyche or not. She just cries and gets so irritated, sniffles, cries. Aaaaah? It scares me, I don't know a normal pediatrician, so I'm going to see a pediatrician tomorrow, we'll see what they say. Has anyone had this happen, can you advise?