What could my daughter have?

I have a 2 1/2 year old daughter. She is extremely smart she isn't slow what so ever but extremely anti social. She dont like anyone touching her or even speaking to her if she dont know them well. It takes her a long time to get used to someone. She will give ppl a dirty look when talking to her and she starts whinning or if they try to hold her she will scream very bad and start crying reaching for mom or dad. Her whole personality changes when she is in an unfamilar area. Like another family members house that she dont know. She seems to do ok with children her age its mainly adults. She also has eating issues she eats unhealthy things such as chalk, leaves, rocks, ashes and cig butts, lotion. No matter where she is at its like she cant help her self. She knows it wrong but she dont care. And another thing I noticed is that she always to be feeling or touching something. If I take something from her she throws a fit.She likes to through her body to the floor usually hitting her head. So I know this was long but just wanted to let yall know what all was going on. Most of this started with in this past year. Some of it has always been there but getting way worse. Like the eating and have to be touching things. What do you think could be wrong with my daughter? Already have an appointment schedule but its not for another week so I am just curious what others think could be wrong?