Disappearing lines......

So for the last 3 weeks I've been so freaking tired no matter how much sleep I get. My breast hurt so bad I dread putting even a t shirt on (forget about the husband touching them) I've been so moody over absolutely nothing and I mean nothing. Me and the hubs got into it over freaking cheese dip and I just start crying out of no where. Just some much at once. So I bought just a cheap dollar tree test. Well I get up Wednesday take the test and as Im watching THERE'S A SECOND LINE!!! So I make my self wait the whole 3 minutes by brushing my teeth and trying to ignore the test....... my timer goes off I turn and look and IT'S GONE!!! THE SECOND LINE DISAPPEARED!!!!! I'm so confused. I swear it was there. I had grabbed my phone and was going to call my husband but wanted to wait the 3 minutes like it said and it's gone. I have never had this happen. Has anyone else have 2 line but at the 3 minute mark it's gone?!?!?! I've been in tears for days and I'm scared to make an appt and it just be a faulty test. Please help.....

UPDATE: Went to the ER from having very intense pains. Unfortunately the reason I had a disappearing line is because my body was getting ready to get rid of the baby. I was pregnant. Again. I lost my baby. 5 1/2 years of trying and now my second miscarriage. I think I'm done. No more trying for me. I pray it works out for everyone else. Baby dust to all ttc mommas out there.....