Some Spanish words come so naturally. Like 'gracias'. Even when I'm in the US, 'gracias' instead of 'thank you' comes out. Then I get the look, like "I didn't know you were Mexican." -- because many Americans know that anyone who speaks Spanish is from Mexico. ;-/
Similarly, with 'perdon', I bump someone in the grocery store or on the street and out pops 'perdon'. 'Buenas' is an all occasion greeting word as well. Sometimes I can't even remember what I used to say when someone sneezed, but now it is 'salud'.
But one word that I haven't stopped saying is 'Oops!' I drop something: Oops. I make a mistake: Oops. I spill a dribble of coffee: Oops. I forget something: Oops.
The funniest thing is that several people who have been around me seem to really like this. Rarely will anyone in Honduras ever admit to a mistake or a goof. You will almost never hear "I made a mistake" in Spanish. It is possible to say that in the Spanish language, but the more common phrase translates more like "A mistake happened to me." In other words, it's not my fault!
I'm not sure how Hondurans mentally translate 'oops' but apparently it is an acceptable manner of saying "I goofed." My nephews really like it and use it a lot, at least around me. When we have a maid or workers here, it usually only takes a day or two before they start saying 'oops', too.
Like me saying 'pucha', it sounds really cute.