4 weeks. Is this a miscarriage or implantation?

My husband and I had a miscarriage earlier this year when I was 16 weeks. We are finally ready to try again and I was late for my period. I took a test and the line was faint but still positive. Today I am two days past when my period should of arrived and tonight I noticed spotting in my underwear that was a brownish pink. I went to the bathroom again 15 minutes later and when I wiped it was light pink. Is this another miscarriage? I’m praying it’s possibly implantation. My nerves can not handle this. 😭