Next testing?

Hailee • Married June 2014. TTC since Aug. Lost baby #1 at 4 weeks on New Years of 2015.
Alright iv taken four test in the past three days. Two faint lines and two neg. Glow says my period is due Sunday but my other app says the 1st. Glow is usely a few days off even when I put in the right info. I'm just wondering when should I test next?