Need help with LEFT HAND POTENTIAL

So, I am quite new to the shredding stuff. I find 115-120 bpm area gives me trouble - which seems far from the demonstrations of lines on ctc, which I’d like to reach myself someday I know I can tremolo pick way faster, so that’s not my concern. My concern is the left hand. How can I test its potential? I am afraid of being stuck at low tempo due to left hand problems My hope for this critique is to give me confidence in my left hand and understand how it develops into faster tempos.