For many years I was a Saxon/Viking re-enactor in Regia Anglorum
https://regia.org/. This has really helped my fantasy writing. It gave me first hand experiences of using a sword, spear, bow, shield etc. All our weapons were metal and weighed the same as weapons from the period. We weren't seriously injured, but I did get fractured fingers and cracked my ribs twice so it wasn't for the faint-hearted.
One of the most useful experiences was fighting in all the armour of a Saxon warrior. Chain mail is heavy and weighs about 40 lb. With the helmet, shield and other accouterments it certainly adds up and on a hot summers day it can be very daunting. A padded jacket (gambeson) is worn beneath the armour otherwise you feel every blow. The gambeson absorbs much of the shock and prevents the chain mail links jabbing into flesh which would seriously hurt. The downside of a gambeson is that you heat up even more in battle. Being several layers of wool, you don't half sweat.
With all this weight and heat, men fighting in armour need to be rotated out of the front line fighting to rest. This is very hard to do in the heat of battle and would normally happen between clashes, should that happen. Shields add to the burden and are also used as a weapon. Inadvertently, in my training days, my shield was occasionally shoved into my face and that hurts. In battle this would have been deliberate. A shield clash in itself is very scary and can break a defensive position.
Rarely was anyone bloodied in our fighting and that has to come from imagination. Someone once pointed out that cutting an artery causes blood to spurt, so spears/swords, axes would have caused horrific injuries and the air would have been filled with a fine mist of blood. Having bitten my tongue I know the taste of blood and it is often described as metallic in taste Imagine, then, the air literally filled with a fine mist. It must have been truly awful. Tales of King Arthur and his knight portray a noble fighting which is very far from reality. Add the screams of wounded and dying men and a battle must have been a dreadful experience.
I have also faced a cavalry charge. The horses were meant to stop in front of our shield wall, but one horse skidded and hit a man in the line. The horse's momentum propelled the unfortunate man about twenty feet backwards through the air...and that was unintentional! If the charge had been maintained then people would have been smashed from the line and bodies flung far and wide. Horses won't naturally charge a line of people but spurs raking their flesh and a compact line of horses will break a shield wall.
I have also faced archers and that is not a threat...initially. Arrows fired into the air can be countered by a raised shield. However, in the chaos of battle with spears coming at you from any direction, the threat from cavalry etc an archer can be overlooked. Archers were to be feared and in later battles when the bow draw strength was typically 100 lb and with a bodkin tip, armour and shield were no longer proof against an arrow.
A further issue I had not considered was how hard it is to kill a man in armour. Many of the skeletons discovered from graves near battle sites show wounds on their arms. It often took many blows to kill a person and broken bones were just as likely to kill given swords rarely punctured mail. Fighting was a hacking process with perhaps little finesse. The advent of the mace was exactly this, a weapon to smash bones.
Fortunately for us, once the battle was ended, there was a call for "Dead Arise" so we managed to survive each and every battle. I pity the poor unfortunates that didn't.