Well, another option is to switch to a bow with flint or fire arrows and lose the iron armour because it's slowing you down. Grab some troll leather, dodge roll and move more so you can avoid being hit instead of trying to tank damage from something that's the size of a house. Shoot when you've got range and don't rush it.

You can drop trolls faster with piercing damage than with an axe so if you insist on fighting them in melee maybe grab a spear instead. I recently started a new character and was able to defeat a troll in cave with melee. I had limited space to move but was using a club which isn't a great weapon and it only hit me once because I made a mistake. I had only leather armour and a wooden shield at the time so parrying or tanking the damage wasn't an option. For the most part once you learn to time your dodge rolls properly, and how to manage stamina, you'll be fine against trolls.

Oh, and it's definitely easier to deal with multiple enemies if you kite them and use range weapons when you have the room to do that. It may take a bit longer, but it's much safer. Keep that rested buff up and make sure you have the right food combo so you have a decent health and stamina balance.