Pregnant while using Mirena?

Could I be pregnant? I've had the mirena since June of last year and the strings had to be cut due to my husband having issues with them, therefore I cannot check them an make sure it is in the right spot. I have not been back to my doctor for a checkup since. At first I didn't have any issues with the mirena no cramping, my face was clear, and I spotted. Now I am having issues with acne, fatigue, severe cramping, no bleeding/spotting whatsoever, sharp throbbing pain in my right leg, headaches, dizziness, nausea, loss of appetite, trouble concentrating, and also frequent urination. All the same symptoms I experienced with my first child. I took a pregnancy test about a month ago and it came back negative; however, with my first child the doctors ran several test which also came back negative. What is going on? Am I pregnant? Are these symptoms of the mirena? Should I be worried if I am pregnant while using an IUD? Someone please help!!! :(