First of all, let’s not call it a “phase.” Calling what you’re going through a phase diminishes what you are going through. What is happening is you are looking at yourself and trying to figure out who you are. That is a good thing!
Questioning your sexual orientation is a very normal thing to do. Gay, lesbian, bisexual and transgender people often have questions. If you are feeling this way today, does it mean you will always feel this way? Maybe, maybe not.
Some people may seem like they’re born knowing they’re gay. But actually, most people in the process of coming out do question their sexuality. Some will eventually come out as gay, lesbian, bisexual or trans, but others will decide that they are straight. Each and every one of these identities is okay, as long as you are comfortable and true to who you are.
Some girls and women only realize they are gay in their teens or twenties, or even later. It’s also normal to feel that your sexual orientation shifts over time.
But whether you are absolutely certain that you are gay,bi, or still trying to figure it out is probably less related to how old you are, and more related to various individual factors. But no matter how long it takes to answer that question, rest assured you are the best person to do the answering, whatever your age.