Thrush

I think my 2 month old has thrush, he has the white patches on his tongue and it's starting to spread under his tongue. I tried wiping it off to make sure it wasn't just formula but it's not coming off. It being the holiday weekend I haven't been able to call the pediatrician yet. Just wondering if there is anything I can do now before I call the doctor tomorrow. Also when I do call the doctor what will the doctor do? Prescribe something?