soreness

Guys I understand that after you lift you can expect to be sore and because of lactic acid buildup. What I want to know is if soreness is because you tore the muscle fibers to stimulate muscle growth or no you can be sore just from lifting alone without any muscle tear/growth?

Three weeks into using Trimix. I’m still dialing in amount. Even on low volume injections my shaft is slightly sore the next day. Is this common? I’ve had 1 injection that didn’t work and I’m attributing that to I missed. Does an injection closer to base work better then mid shaft or...