Yes, it is absolutely okay to ask your therapist for longer sessions if you feel that the standard session duration (usually around 50 minutes) is not sufficient for you to fully explore and address your concerns. Therapists are generally open to discussing session length and scheduling options that best meet their clients' needs.
Therapy is a collaborative process, and the goal is to create a safe and supportive environment where you can freely explore your thoughts, emotions, and issues. If you find that it takes you some time to "warm up" and get comfortable discussing significant matters, longer sessions may be beneficial for you.
Bringing up the topic of extended sessions with your therapist can be as simple as expressing your feelings and needs during the therapy process. For example, you can let your therapist know that you often find it challenging to address important issues within the current time frame and that you would like to explore the possibility of having longer sessions.
Keep in mind that therapists have their schedules and may have limitations regarding session lengths, but they will work with you to find a suitable solution that supports your therapeutic progress. They may be able to accommodate longer sessions occasionally or on a more permanent basis, depending on their availability and practice policies.
Being open and honest about your preferences and needs in therapy is essential for ensuring that you receive the most effective and helpful support. Remember that therapy is about your well-being and growth, and your therapist is there to support you in navigating the process in a way that works best for you.