Your going to stand out from the first. Unless your uncommonly short, thin, undernourished, dirty, toothless and have very tough hands and feet your going to be a rare bird.

While there may be one or two as tall, assuming your only 6' or so, your going to tower over the crowd. Your likely to be far better in better shape than the average. More muscular and generally healthier. The peasants are strong in a bandy, wiry, enduring sort of way. Your also going to be far more sensitive to cold, dirt, pain, irritations, abuse and hunger.

Clean, well fed, even just relatively so, with teeth after the age of thirty, with soft hands and feet, and wearing shoes? That would make you an exception and pretty much resemble a noble or clergyman.

Modern mannerisms like looking directly at people, standing straight and walking with head held up also makes you look like someone with status. You might try to fol people into thinking you were from the church or a noble. But if the illusion falls through your dead.

In 1000AD it is a tight society. Clergy and nobles split, often contest, power. If your not one of the above or one of the few merchants your with the other 90% of the population, a peasant. Peasants have no rights. They have no recourse or opportunity to redress wrongs. In fact neither clergy nor noble could do any wrong to a peasant. Everything was allowed. Rape, murder, torture. That is unless the clergy or other nobles object.

As a serf your duty is to produce for the landowner and/or church. During any of the many minor and great wars your forced into service by the thousands where your duty is to wear out the main combatants sword arm by allowing they to swing their sword at your unprotected body. Technically your not even allowed to harm your betters on the other side. They were captured and ransomed. After the battle dead peasants weren't often counted. We have little idea of how many fought or dies in many major battles. Dead peasants were dropped into mass graves.