Sure, to some extent as it will measure frequency response. You don't want any or as little room reflections as possible, optimally only the speaker. In one of F. Alton Everest's books, he suggests a substitute for an anechoic chamber by using the outdoors during a still, quiet time. Preferably, you would be on top of a hill or a slope with the ground dropping away from the speaker being tested. But if it sounds OK, you probably did not damage it.
Last week, I got a Alto Truesonic TS210 550/1100 watt powered speaker to use as my stage keyboard amp/speaker combo; it's only 20 pounds! (I finally got tired of dragging my Peavey KB300 up and down my basement stairs). While I was testing it out, I thought I heard the tweeter making harsh resonant sounds on some sustained notes at full power. I stuck the offending organ key down and walked around the room only to find a decorative temple bell zinging away. (I can get all sorts of stuff to rattle). Moral of the story, don't blame the speaker until you eliminate all possibilities.