Braxton Hicks?! Or contractions....FTM

I have these sharp Charlie horse feeling cramps in my low back & my stomach tightens up...sometimes they last only 10 seconds others 30...

Sometimes the cramp will go down one leg and I can’t put any weight on the leg for those seconds. Is this a contraction or Braxton Hicks ? Confused by the leg cramping up as well....please help!