I had that a few years back, hard to get rid of. Just make sure to breath normally when it happens and try to do something else to keep your mind from it. I actually rushed to the hospital when it first happened, not knowing what it was
Another good advise is to put a long tube/pipe in your mouth, e.g. a plastic pipe you used to shoot paper stuff out when you were a kid, and breath in and out.. or just go out and walk a few blocks that helps too.