Yeah it is in the wrong forum but no worries, someone will eventually move it.
That phenomen is kind of common when taking a huge step in terms of hardware upgrade. TV monitors do not care about latency very much at all so you probably got used to hitting earlier than visually indicated to account for the delay by the TV monitor.
The gaming monitor will have a very short response time in comparison but you are still hitting early due to your habits.
From my experience with similar cases: Just let 2 weeks go by and see if it is still a problem. Most people adapt to the changed hardware within a few hours of gameplay although it takes a while to be 100% on time again.