Spotting ! While pregnant

Hi everyone I just need your opinion and help! I had implantation spotting before I found out I was pregnant . Then on Saturday I spotted light pink and after that I have not stopped spotting and itsMonday now . It’s turned into a light brown but I still don’t know if I should be worried I had a miscarriage in March so I’m scared . I went to the ER and they didn’t have any answers for me . They said they couldn’t see a sac because it was too early I’m 4 weeks.

Please if anyone has any similar situations please tell

This is it now