If your enemy won't let you get an attack through, press E to kick or shield bash to break their defense.Combat can be tricky to get the hang of for new players - you'll need to get used to seeing which way an enemy is preparing to strike and react accordingly to block - and keep yourself from getting overwhelmed whenever possible.Sometimes if your speed is almost even, it will take forever to chase them down unless they're also looking for a fight - and waste valuable time, or let them regroup with others to bolster their numbers before turning to face you.
Trying to do everything on your own will get very hard otherwise.