To be fair, the use of midazolam is ultimately up to your healthcare professionals. It's not required and may be skipped if they think it would be harmful (age or respiratory / nervous system health) or is unnecessary (no anxiety). It's almost always given as an IV drip 10-ish minutes before wheeling you around to the OR, which is how you'd recognize if you got it. It's just a very common practice to give it by default for most people under 65-ish.

You may also require either a higher baseline dose than expected, and an onset of acute anxiety can actually affect dosing too. Both totally normal!

Either way, it's best to speak with your doctor leading up to surgery if that experience was upsetting. There's lots that can be done for dosage, supplemental medication, etc. Your comfort is important!