My dog is coughing like there is something stuck in her throat but there isn't?

about 20 minutes ago, she started coughing about ever 10 seconds as if there were something stuck in her throat. Now, she keeps coughing every 3-8 minutes. It's not choking because it's been 20 minutes. It looks like she wants to throw up but nothing comes out. I really don't know what to do. She's breathing perfectly and she's walking and running/trotting fine. I'm just still a bit worried, what can it be? turning 2 in november, she's a maltese and we got her from a breeder not a kennel. Right now she isn't really coughing anymore but what could it be. Please don't just say "go to the vet" i'd like to know if I really need to.... thank you...