how long is to long to spot

So on the 1st through the 9th i Bleed but it wasnt enought for a pad and barley a liner it was only when i wiped and i was dark brown sometimes light pink or light red it stopped for 8 days On the 14th I Went To The Er Cos I Wasnt Feeling Well Negative pregnancy In the Blood Test The 17th Came and im spotting again and been spotting since but this time its way more lighter its like implantation but its going on to long but idk my next step to test again or what??? any opinions?