What's wrong with my chicken?

Hi, I am new to Backyard Chickens. And I do not know whats wrong with my chicken. I don't know the breed of my chicken. She is all white with a red comb and wattle. She's about four months old and over weight.

She has been making weird noises like a rasping cluck. I'm not sure how long this has been going on, but today I came home and I noticed that she was still making those noises but they were quieter and she wouldn't make her habitual loud sounds when she sees someone she knew. She also made the noise and squirted a small amount of watery poop, but I only noticed her do that once. She laid an egg earlier today, so far she has laid about eight eggs and she started this month. When I came home I saw her eat and drink. I had a friend take care of her today since I was not home. So she didn't notice anything strange about my chicken and she has been around my chicken since I got her. I had her since she was two weeks old. She is a free ranging chicken and we have tomato plants in our yard. She recently showed interest in the fruit so we put a cage around our plants to protect her from the leaves that can harm her. And when I came home my friend removed the fence and my chicken could of eaten a leaf or something. She had mites but I used diatomaceous earth on her and haven't seen the on her since. Could she have Gapeworms? I tried to do the best I could to tell you what has happened that could cause her to be ill. I'm am really worried about my hen so please help!

Check for other symptoms, is she stretching out her neck? Does she have a runny nose? Is her comb paler? Sometimes you can see the gapeworm by looking down her throat and they will stretch out their necks more. If the rasping sound gets worse it could also be a respiratory infection. Without more clear signs it is hard to guess.
If her only symptom is the rasping cluck maybe she just has something stuck and you could give her a small amount of olive oil and help massage it down her throat. Sorry I couldn't be more helpful.

I have just fed her and put diatomaceous earth in her food hoping it can kill any worms, if there is any. I noticed she has been going into small spaces and lies down. Her comb and nose appear to be normal. I was not capable of getting her to open her mouth so I can see her throat. She makes a noise every breath she takes. I will see if the diatomaceous earth has any affect in a few hours and if not I will try to put olive oil in her throat.

Thank you, but she hasn't gotten any better. What should I do?