Has anyone had a bad experience switching gear brands?

Went through 20ml of Tren E 200mg with no issues, no pip. Went from .5mg twice a week to 1mg twice a week. I have been pinning together with 1.5ml test cyp, this gear has not changed and I get no pip.

Switched to new brand last Tuesday, pinned left delt and had immediate pain, to the point it was difficult to hold my arm over my head. This lasted 2ish days. Come Friday, pinned the right delt. The pain was maybe a little delayed an hour or so, but ended up being worse, still today.

What is everyone's experience? I have read all kinds of things online from over-dosed gear, high BA, oil that doesn't work with me...

Should I try another bottle, try smaller dose, can I dilute with sterile oil?

Thanks BOP