Pregnant?

I got Mirena iud on May 24th. I have not blead at all yet and I've been sooo nauseous. I have head aches and I'm so tired. Yesterday I nearly slept all day and ended up sleeping till 11 today! My stomach has been really weird. I took hpt and got two positives and two negatives. Went to the doc and they did a blood test and it was negative. I've read that qualitative blood test and be false negatives if it's to early. Yesterday I had really weird pain and went to bathroom to check my Mirena strings and they are longer then before.... I'm very weak feeling throughout the day and can't hardly eat anything. I feel pregnant but I'm not sure. I have a lot of crazy symptoms that just grow! What do y'all think?!?