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It sounds like a running position/technique issue.
Check your stance and start position.
Are you over extended?
Pro Episode #16 – The Dreaded Low Back Pump Out
What is your foot strike when you run?
Episode 305: Solving Problems With The Tunnel: The Foot Strike
Going to a more minimalist shoe asks more out of your posterior chain and your ankle rom.
If there was a big difference in your prior shoe and the new one purchased this could be an impacting factor.