You can't analyse your own technique, that's why we have coaches and trainers. You're in the middle of a big effort, you're too busy trying to get the fucking weight up there to notice little details. As well, it's you, and nobody looks at themselves objectively.
Lastly, your technique may or may not be "wrong", but it may reveal weaknesses, weaknesses which are holding back your bench.
So get someone else to look at your technique.
With or without that, remember that rep ranges are merely guidelines. They're not engraved in stone. The important thing is always to do more than you did before, more weight or more reps or more sets.
An easy way to go for this is "debt reps" - whatever was your target reps, whatever you're short, do that many reps afterwards, and then the same again - however many sets it takes. For example, if you were meant to do 3x8 and got 8,7,5 then you are 4 reps short, so you owe 8. You do 8,7,5...4,2,2.