Blue Tongue Skink w/ Foaming Mouth?

I hadn't handled my blue tongue for a couple weeks and now she is seeming very out-of-habit. I took her out of her cage and she huffed and hissed more than usual until I noticed that she was foaming a tiny bit at the mouth. Is this because she was so aggravated, or is it a health concern? I want to know before I go to the vet and spend tons of money on unnecessary tests that could be traumatic for her. I am extremely short on money. HELP ME PLEASE!!