My first and only dm was a huge dick

The start of the campaign village is being attacked, I picked a swordsman cus swing sword is easy probably good for a beginner

Anyways I roll a 20, DM hypes it up saying I have impeccable footwork, draw the blade from its sheath perfect, doing this epic buildup for about a minute or 2. Then he flatly says I miss my perfect swing because every enemy was 200 feet away

That was in middle school and now my GF is trying so hard to get me into Baldurs Gate and now it’s just a matter of me doing some DnD homework about classes and other stuff so I’m not going in 100% blind