Almost 2 weeks ago, I took a pregnancy test and it showed up Positive. I'd taken a few before and after that, and they all came up Negative. The positive result was on an EPT digital test. The rest were different tests, line and Clearblue. I then went to the doctor to get tested, and the urine test came back negative, and the blood test also did. I'm still having back aches, stomach pains, and pressure in my lower stomach. I've been having headaches and have gotten dizzy a few times. Also, every morning I feel nausiated but then it goes away within an hour or so. These symptoms aren't in my head because they keep getting worse! I could barely sleep last night. Plus my back has been killing me! I'm not sure what else this could be. I only got the 1 positive pregnancy test, so im not sure! Could I be pregnant? Or did I possibly have a miscarriage? NO bleeding and NO cramping other than pressure in my lower stomach like I said.

Any suggestions?
Thanks

Also, my periods are VERY irregular, so im not even sure when i've missed one or not!