It is not at all unusual that a young man should ask this question of himself as most young men are attracted to a male friend in early teen years, a type of hero worship due to their sporting prowess or some other ability that they may have.

We always wonder if we are the same size or shape as other boys and secretly wish to be able to compare, but most of us found this to be a hard question to ask.

You may have gone that little bit further and found out the answer for yourself, you may have had a sexual thrill at looking or touching, you may have had an erection and masturbated, this does not mean that you are gay.

This shows that you are a normal guy and doing what is normal but not spoken about, one of your life experiences.

The information below is taken from the website,http://www.avert.org/hsexu2.htm
Where a much fuller explanation can be found.

Am I gay?

Many people have feelings towards other people of the same sex, and wonder whether this means that they are gay. For many people these feelings can be very intense and alienating. Some people who are attracted to other people of the same sex are gay and go on to have sexual relationships with people of the same sex. But other people who have gay feelings find that these change over time and they become attracted to people of the opposite sex.

When do people know that they are gay?

There is no simple answer or standard answer to this question, as it varies from person to person. Generally it can be said that being gay is not something a person suddenly begins to consider, and it may not be something they can initially put a name to. Research published in 1996 showed how the young gay men interviewed had described a set of feelings which they gradually realised made them 'different' in some way, and a set of feelings they thought maybe every teenage boy has.
There is evidence that for some people homosexual experiences may well be part of a transitional or experimental phase in their youth. This is hardly surprising given that adolescence is a period of change in which many people find who they are and what they want for themselves in adult life. This kind of behaviour is perfectly normal.

Are you born gay? What causes people to be gay?

There is no simple answer to the question, 'Are some people born lesbian or gay?' There are some theories which stress biological differences between heterosexual and homosexual adults, suggesting that people are born with their sexuality already determined.
. At the moment it is generally thought that biological explanations of sexuality are insufficient to explain the diversity of human sexuality.
What is clear is that people's behaviour is influenced by their family environment, their experiences and their sense of themselves. Beliefs about sex are initially shaped by family values. Later on these beliefs may be shaped by pleasant and unpleasant experiences of sex and also shape their choice of activities and partners. Throughout their life a person's sense of who and what they are has a strong impact on their sexual development and experience.

Can you stop being gay?

There is now growing general support for the belief that sexuality is pre-determined and may change over time, or remain fixed. However, many people are interested in whether sexuality can be altered solely by a person's desire to change. Organisations that help homosexuals attempt to change their sexuality can be generally divided between those that use psychological 'reparative' methods and those that use religious 'healing' methods.
Some people believe homosexuality is an illness and believe it can and should be cured. Many of these 'cures' revolve around psychological therapies (often called reparative therapy) which endeavour to re-orient a homosexual sexuality to heterosexual. Although there is little scientific data to evaluate, what is available seems to indicate that reparative therapy is ineffective.

There are several websites that will be very helpful in answering this question,

http://www.avert.org/hsexu2.htm
http://www.puberty101.com/p_amigay.shtml (A question & answer site)
http://www.netdoctor.co.uk/menshealth/feature/amigay.htm