Remember how it felt to be a teen?

Those years can be a swirl of emotions and challenges.

If you have a teen in your life, you're probably experiencing those feelings again as you watch them try to navigate through their own teen years.

Teens are on a path to independence.

And that means the kid you've known may turn into someone you don't recognize as much.

So how will you know if those changes could be signs of a problem?

Here are three signs that could mean your teen is struggling.

One. They're doing something harmful.

If your teen is self-harming or talking about suicide, it's important to get help from a counselor.

And if it's an emergency, get help right away.

Call the Suicide and Crisis Lifeline at 988.

You can also reach out to the National Alliance on Mental Illness at 1-800-950-6264, or text NAMI to 741741.

In Canada, resources include Talk Suicide Canada.

That number is 1-833-456-4566.

And watch for other signs of harmful behavior in your teen.

For example, are they using drugs and alcohol in harmful ways?

Two. They're doing things that are risky.

Watch for behavior that puts them or others in danger.

This could include having unprotected sex, sexual relationships with multiple partners, or a string of relationships that don't last long.

Or their driving may be reckless.

Or they may be getting into fights.

Three. They've made sudden, dramatic changes.

Anyone can have a bad day, but if your usually calm teen is suddenly having angry outbursts, it could be a sign of a problem.

Also look for other big changes, like new friends who seem to be negative influences.

Or there could be big changes at school, like lower grades or skipping classes on a regular basis.

Keep in mind that all families have different ideas of acceptable behavior.

What's important is knowing what's normal for your teen and watching for any changes that seem out of character for them.

If you're concerned about changes in your teen's behavior, get help as soon as you can.

Reach out to a doctor, counselor, or other health professional.

You probably experienced some of the same things your teen is going through now.

Let them know you're there to listen and support them whenever they need it.

And try to remember that being a teen is temporary.

Work through this phase as best you can.

Together, you'll get through it.