Walgreens Test anyone?

I took this on 12/26 which was about 3 days late for Af. It came up immediately and I haven’t taken another one since this one was so dark. Now I’m worried after reading a few reviews. Still not Af and only symptoms I have are nausea here and there and being tired. I miscarried twice in 2015, had two failed ivfs in 2017 and haven’t naturally been pregnant since 2015 so I’m sure you can understand why I’m a bit worried. Anyone use this test before and it be accurate? Thanks!! 9/2/18 is my due date based on LMP.