Primo has a little bite lol
Shot my first shot of Primo E and some Test E. Total 1cc of Primo E and .5cc of Test E. Right after the shot there was definitely a noticeable "pressure". It also built up as the shot went along. I shot into my Lat. After working out and a hot shower it dissipated a lot and is fine now.
Didn't realize Primo had some bite to it. On Primo only days I may dilute a little with GSO.
I am assuming you don't get used to it like virgin muscle turning to non virgin muscle some chemicals are just heavier and are that way??