Hi.
You need some testing , for thyroid, diabetes, and also a full blood count.
You also need a referral to a gastroenterologist, a doctor who looks at stomach problems.
Its so hard to say what this could be , as further testing needs to be done to get a diagnosis, as this could be one off many conditions.
You are only young, you need to go and see your doctor and tell him what is happening, as you need this sorting, so you can lead a normal life, you shouldnt have to keep going resting in the restroom.
This needs sorting.
Please go and see your GP and he will be able to run some tests as well as give you a referral to a consultant.
I would see a gynecologist or at least your primary doctor. You have multiple symptoms and actually, a doctor is the only one who can really help as he/she will run some tests and take your history, etc.
Good luck. Hope this helps.
Are you sexually active becasue if you are it could be a sign of pregnancy, a close friend of mine had similar symptoms and she took an at home pregnancy test and it came out positive she then confirmed with the doctor and she was pregnant. Best to talk to a doctor. Hope it helps good luck