Switching pills?

*I do have an appointment with my gyno, she's just currently out of town so I have to wait until the end of next week so see her.
Anyway, I've been on the same birth control (Lo loestrin FE) for a few years now and well my question is, does there come a point where it just stops working, so to say? I've noticed that I've had breakthrough bleeding about 10 days before my period is actually supposed to start for the past couple of months and have been getting bloated way to easily now. On top of my cramps coming back too. Could I possibly need a higher dose of birth control? I would just like to know what some of you ladies think before I go and talk to her about it... Thank you girls in advance!