24 weeks, noticing some bleeding... Please help!

I wish I could post more positive and less concerns but my doctors office is closed because it's the weekend. So looking for some advice...

I have noticed the past 2 days the tiniest spot of brownish discharge on my underwear. Should I be concerned? I've noticed my baby hasn't been moving as much lately. I have been running around like crazy. I've noticed this discharge after I have worked out. Is this normal or not normal? Not sure what to do..