You get used to getting back in the zone quickly or you forget about getting a paycheck.
I'd love not getting interrupted as a senior, but the fact that I am a senior is exactly why management, staff and customers zero in on me. I get annoyed if they ask me questions whose answers they could have easily worked out themselves. I not only give them the answer, I tell them how to go about figuring it out or looking it up and hopefully, that's the last I see of them until they interrupt me again. I prefer getting a lot of short interruptions that I can quickly deal with. None of us is immune from interruptions. The CEO will slam the door of his office to signify to the rest of us peons in the strongest possible terms that he is not to be interrupted, only to have his landline phone ring from behind his door within 30 seconds :) Serves him right.
My attitude is, as long as they pay me, I don't care if I am interrupted. If I hand in a deliverable late because I've been interrupted a few times more than usual, it is what it is and I pass on the missed deadline to management as their cost of doing business. I can't really afford to be negative about being interrupted. We work as part of the team and anything I do to support the members of the team as well as the team as a whole - that's at least as important as my own individual tasks.
Sometimes, the interruption works well for me. I may be bogged down on the issue and the interruption gives me a chance to look at the problem with fresh eyes and work out a different approach.