I agree with the 1st reply that you need to determine for yourself why the title matters to you. If it's important then communicate to your manager the importance.
Now, when you say "I feel like I'm just a secretary" tells me that you are looking for more meaningful tasks/projects (as you perceive it) that would make you more happy and perhaps increase your pay at the same time. It could be something new you want to do or, as you said, do real full stack engineer assignments. Regardless of the title there will always be mundane tasks that you would have to do, which would make you feel like you are not doing something significant, but they are an essential part of the job, and should be reflected positively in your reviews. If you are on good and open terms with your manager I would communicate your feelings to them directly: "the tasks I've been doing are very mundane and make me feel like a secretary".
Can you try to automate those tasks somehow?
For better pay, you need to solve problems, small or large, which will be reflected in your performance review and can lead to a promotion, pay increase or bonus increase. For instance, can you automate the "secretary" tasks somehow, fully or partially? This would be one problem you can try to tackle and transfer the automation to a lower level team member, while you love to higher level tasks.
Hope that helps.

Edit last sentence: ...while you *move* (not *love*) to higher level tasks.