What would you do in 1000 AD Europe?

I'm a twenty-three year old man, In my pocket I have a small penknife, and a handbook of edible plants. I imediently find a flowing river, which, to the best of my knowledge is usually clean. I soon find a small cave lodged in the side of a hill, and declare it my home. I then start to make a fishing spear, using my penknife. Its thin, and long and I am soon proficient in spearing fish in the river. Large salmon are my usual food, and I soon turn my mind to other matters. I build a wall out of entertwined sticks and mud, and enclose my cave. After a short time a lightening storm hits the area, and a small forest fire erupts. It is soon put out by the raging winds and rains, but the next day I find some small embers in a burnt out tree. I use the embers to start a fire in my cave, and soon I have a constant fire. I use it to cook the fish, which is an improvement.
I then start on making bows, experimenting with different woods and strings. I end up with a willow bow about four feet long with a entertwined bark as a string. I soon kill multiple birds, rabbits and other small animals, and soon move on to bigger prey. After killing my first deer, (It was a small doe) and I tan her hide and turn it into crude clothing.
After several weeks the trees around me are completely stripped of branches, wood I used for my fire, and in order to create a more habitable living space, I strip the bark off the trees, killing them. I then drag the disintergrating wood away from my camp.
During hunting, I search for wild oats and other plants, using my edible plant guide to figure out which is which. I soon find the valuable plants, and plant dozens of oats around. I soon have a small farm going, and at the end of the growing season I harvest the oats (Which are meagre without proper sowing or irrigation). I then start scouting out the area around me, until I find a local village, some 15 leagues away (Leagues being an hour of walking)) I trade the wheat and sell several extra bows to make a large sum of money. I then hire several unmaimed beggars (For a small amount of money, they are homeless and starving, after all) and also buy a small amount of iron tools. I set the three beggars to continue clearing trees and the rest to cultivate the land.
After three more years, after my farming has massively I have hired several more men, none beggars, to bring in their trade and have started a small population. I have dammed the river and started a settlement much richer then then the surrounding towns because of almost non-exsistant taxes.
Soon after this a Italian city state starts raiding trading convoys, and I soon have to train a professional army. my town population swells to over twelve thousand, and my army is almost eight hundred. I soon take over the other small villages surrounding the area, and bring prosperity to them. I use the new population and taxes to create a larger army. I also start to slightly increase taxes, in order to create a welfare system and a larger army. I slowly but surely take over more and more villages, and eventually another city. I forge alliances with other city states, and then invade stronger enemies, and start to invade all of southern Italy. Soon the small river village has swelled to a large fortified city, with massive amounts of gold pouring in from surrounding villages and cities. Taxes are still lower then all other city states, and craftsmen commonly abandon their former kings and join my own city states in order to have a more succesful buisness. Soon, I have a trading hegemony, for Italy is perfectly located to trade with the middle east. I soon become a large country, and dominate the italian area.


(Now, I expect you reviewers to point out every single mistake I made, and anything unbelievable, point it out!)