Managing a Career Shift while Respecting my Current Employer

I have a job that meets quite a few of my needs, but it's ultimately not the industry or the type of work I want to be doing long-term. I have a wonderful relationship with my manager and coworkers, and they generally know that I really like this job, but it's not my dream career. I've recently applied to a job that is a perfect fit for me, and I think I am a pretty competitive applicant. However, I understand that it's very competitive in Computer Science right now, so it's no time to jump ship. Simultaneously, my obligations at my current job are starting to ramp up, and I was asked to do a little bit of work travel next month. We are a small business, so that's quite an expense for them. Even if I get a job offer, I would still give my all at these events, but I really don'twant to screw them over. I just need some advice on what I should and should not commit to and when I should mention things to my current manager to keep our relationship positive. Or am I way overthinking this, and changes like this happen all the time?