Sorry you aren't feeling good. So, strep throat is exactly what it says , strep bacteria in the throat. It has symptoms like intense pain, fever, headache and stomachache. There are other things that happen to the throat like a virus that can cause the symptoms you have or tonsillitis which is bacterial but not strep. If your family has been checked for strep and were negative and they also didn't have anything else that warranted antibiotics, then the doctors they saw determined they most likely had a virus. And viruses are contagious and that would explain why you now have the same symptoms as you likely caught the virus. That's probably what it is. However, to be sure, if you are not well shortly, you can go to the doctor yourself and have your throat swabbed. That will tell them on the spot if you need antibiotics or not. In the mean time, try ibuprofen which reduces swelling and gives pain relief and the old remedy of gargling with salt water. Hope you are better soon!