The cough is not something that always happens and a lot of people like to use it as a rule of thumb.. although it's most common with Trenbolone it can happen with just about any injection.. I've had it happen with testosterone before.. it's really hard to gauge your situation, at this point you can better assess it over the next few weeks.. my suggestion is to use the new one that you have and just see how things play out for you over the course of the next several weeks.. I would personally contact The Source in which you receive the items from and speak to them about this.. naturally they're going to defend their product but it's a good place to start, make them aware of it and take it from there..then I will check back in with them over the course of the next few weeks and let them know your progress with the different brand.. this way you exhausted all resources with giving everything a valid attempt..
You did say that you notice good progress but there was a big difference with your injection today compared to things in the past so you do have a lot of things going both ways..
Stick the course give it a couple weeks and take it from there.. I'm confident that you're going to make the right decision and everything will come crystal clear!
If you need any assistance feel free to contact myself or any of the other moderators and the community, we will be more than happy to better assist you with any questions or concerns that you may have..