I’m wondering if my sister is on Methanpetamine?

My sister has recently moved out, and she has lost a lot of weight recently also. She has also told me that she has tried Meth once about two months ago. She said that she did not like it but I do not believe her. I was wondering if someone knew the symptoms of someone just starting to do meth. She also comes over randomly to say hi and will eat a bunch of food and then go to sleep. Also before she moved out I found a cracked piece of light bulb and a straw in her room. I was also wondering if it was meth or if she might be doing a different drug. Any help would be appreciated.