If you have been in therapy with her for two years and don't feel comfortable asking these questions about your treatment (why sessions are shorter, etc.) that's definitely something to address, with another therapist or her.

I think you have two years of history we know nothing about, and we only have a tiny bit of problematic information, so it's important for you to try and be objective AND go with your gut, deciding what's best for your mental health.

No matter who you see, her or someone new, it's critical to be able to discuss it when you don't like how you're being treated in a relationship, aside from an egregious case like assault where there's no need to discuss, you just need to go.

I hope this works out smoothly and for the best, it sounds so upsetting.