Scared and confused

It's 13 days till my cycle. For the pass 4 or 5 days I have had more and more cervical mucus. Today its stretchy. I put some on my fingers and it stretched without breaking. My breast are extremely tender and sore and painful. I have been getting bad headaches, gas, and cramps/bloating. At this point I'm very scared and confused. Please help!!! Any advise helps