My Bearded Dragon is acting weird

Question
ok she is two years old, although i have only had her for about a month * I bought her from a guy on craigslist* any way she is really jumpy, she has food, water, lighting, etc. I am watching her from my bed and she seems to be opening her mouth and making a hissing sound. I thought maybe she wanted to be held, but she is hissing at me when i try to pick her up. She is also scratching at the glass of her tank as if she is trying to escape. Additional Info.: the guy i bought her off said that she might have been pregnant, but she isn't getting larger.

Answer
Hello Alexis,

If you can review your tank setup with me, that would be helpful.
What type & brand of UVB are you using, a fluorescent tube bulb or a compact/coil light?  
What type of thermometer are you using, a stick on type, a digital probe or a temp gun?  Currently, what are the temperatures?
She could be gravid, if she was kept with a male so I would keep an eye on that for sure.  If she is gravid hopefully she wont have any problems.

Does she appear to have metabolic bone disease that you can tell?
The hissing is simply a behavior by them when they either don't feel well, or just are not happy.  

Do you have any pictures of her?

Tracie