I just bought a new Samsung Note 9 (Exynos 9810). Little did I know that the model I ordered was the EU version and not the US version, so the charger I received was unusable with any of my power sockets. I ordered an adapter online but thanks to my impatience, instead of waiting for the adapter - decided to just charge the new device for the first time with my old Asus Zenfone charger. The Note 9 charged pretty slowly, even though the Asus charger is a fast charger (5V, 2A or 9V, 2A similar to the Samsung's 5V, 2A or 9V, 1.67A). I charged it to 100%.
I've been experiencing pretty average battery life, which is weird since the Note 9 has a 4000mah battery. I have however been using the phone pretty heavily as I've been setting it up with my accounts. Did using the non-OEM charger for the first charge-up of the device - mess up the battery performance in any way?
I've been beating myself up over this, so I decided to do a Geekbench battery test (Partial Discharge), which returned a score of 4653 with "Medium confidence", which is lower than the score posted online (approx. 5000) However, I don't know if the online scores are for Partial Discharge, and the comparison scores my phone displayed for example for the Galaxy S8 were also lower on my phone than the ones posted online...
Am I worried over nothing? Would charging the battery for the first time with a non OEM charger hurt the battery/ phone? Is the battery charged at the factory with the OEM charger before it is sent to market?