Implantation bleeding still negative

Hi so today makes day 4 of last implantation bleeding and I still am having a negative result I used morning urine. Is it possible still to early for results?? My period is supposed to be in 7 days on one app and this app says my period is supposed to be today. When should I test again? If I test again tonight will the results change? I spotted for four days and when it stoped I got very light sticky discharge.