So sorry to hear about your concerns. It can certainly be terrifying to have concerns of an unwanted pregnancy, and I am sorry to hear that you are so anxious about all of this, although it is certainly quite common. The good news is that pregnancy tests are quite accurate. If you have taken multiple tests and all have been negative, the odds are good that you are not pregnant. Additionally, if you have had your normal menstrual cycle, that would also indicate that you are not pregnant. Of course, some of the other things that you suggest could be due to pregnancy despite everything else, and they could also indicate some other medical issue going on, and so I would advise you to please speak with your doctor
about your concerns. He or she will have more accurate testing methods that can be used to help determine if you are or are not pregnant, and he or she will also be able to help set your mind at ease about the whole matter. Please use caution in multiple manners when having sex, always use protection, and please speak with your doctor about your medical concerns for more information.