I've been craving Salt, Ice, and burnt food! HELP!?

OK so for the past few months I've been pretty sick with nausea and camping. however the doctor's haven't been able to diagnose me. A couple months ago I started taking multivitamins because I thought maybe i was lacking something and they would help. however they haven't made a difference.

My biggest worry is the cravings I've been having. especially salt and ice chips! but also. you know how if you burn cheese onto a pan in the oven? it gets all black and crispy and tastes like dirt? I've been craving that too.

I haven't eaten any non food items (like pica) but I've been craving the smell of old books, dust, and gasoline. I sometimes think about eating dirt and rocks but I know its not safe or healthy. I've never in my life had these symptoms before and I know Pica doesn't just happen all of a sudden.

I was wondering about Addison's Disease but I can't find much about it.

Has anyone else ever had these issues? or know what it might be?

Thanks :)

**also this sucks because I have bad dental health, so I can't eat the crunchy foods I would like to. Like burnt cheese crisps that taste like the oven or pan** The cravings are soo sever that it scares me D: