Hi, Ceyine,
You should get a sonogram done referred from your doctor or from a clinic. That lump could be a simple cyst of the sign of something worse. Get a second opinion, and get some lab work done to check your blood sugar, o to discard the possibility of having anemia that might be causing you the feeling of tiredness and those other symptoms. Sometimes hormonal problems, can cause breast soreness. Good luck
First, you know you can take a simple and inexpensive home pregnancy test to see if you are pregnant rather than going to the urgent care? It sounds like, though, that it was a good thing you went this time as you had something you needed antibiotics for. UTI's can be painful! You very well could be in the throes of pms as those symptoms sound like that. Wait until your period is supposed to start, then take a home test. If it is negative, wait one week and test again. good luck