Mysterious creature at firewatch

Mysterious creature at firewatch. -Ghostzlayer00
English is not my first language so please bear with me!

This happened about a week ago and i just have to put it out for people to hear. A little info to set the scene. I live in the northern part of Sweden, on the countryside away from the bigger cities.
I work as a Harvester and Forwarder operator with two collegues, and if you dont know what that is, its big red machines that harvest timber. And when its summer time and the ground is dry, its a big risk that the machines chains and tracks grinds up towards a rock and sparks a fire, so on this day i was working as a fire watch to make sure nothing like that happens. I have an ATV with fire extinguisher and water tanks on the back to put out fires with.
So, the story begins
It was around early noon and my co-workers was driving around and i was standing just observing from a far, to my right is the logging road with all the timber stacked, and to my far left is the newly exposed tree line.
I was just observing the machines when i got the sudden urge to look to my left, but i couldnt see anything, just the trees swaying in the wind, i scanned the treeline intensly but i dont really know why.
Suddenly i spotted something behind a medium sized rock or boulder. It was a tall dark shadow, at first i just thought it was an old rotten tree or something, so i started my atv and proceeded to approach it.
The closer i got the more nervous i got. When i was about 40-50m from this thing i could start to make out shapes, as said before it was tall and dark, maybe 3 meters in height, it appeared to have arms but it was really hard to see, i didnt want to but i felt an urge to aproach it more, and so i did.
I was really scared at this point and just wanted to turn around and get the h*ll out of there. I stared at it intensly for like 1 minute, but it felt like hours, and then suddenly it just shrunk down behind the rock, which made me jump a little. Now i got sceptical thinking it was someone messing with me, so i turned off my atv and started to walk towards it, when i arrived i took slow and quiet steps and started to peer around the rock. But there was nothing there, and this made me very scared because i didnt hear annyone run away and i didnt see any footprints or any disturbance in the vegetation.
So i turned around and ran back to my atv and booked it away fast. I do not know what i saw that day, but it still freaks me out, i told my co-workes but of course they thought i was playing a prank on them.
I can assure you that this was very real, i will not blame you if you don’t belive me. Ive been back there since and havent seen anything else, but i still get the creeps everytime i look towards that specific treeline.