Last sunday I had a lesson at a place I hadn't been to before. While I was riding, I noticed Roxy was coughing pretty badly. She would stretch her neck down and cough, almost like she was choking but she definitely wasn't. I thought it was strange, especially because she didn't slow down or act uncomfortable at all. The footing there is weird, so I just figured it was the dust from that that was bothering her. When I went to ride her the next day though, she was coughing again. It's been really dry lately so I thought it again might be dust, but it poured the last 20 minutes of our ride and she still did it once or twice. Yesterday when I rode, she was coughing pretty badly. She was full of energy, so I finally decided to let her just fly around the ring for a few minutes so she could calm down a bit. After a couple times around, she starting coughing but every time I'd loosen the reins so she could cough, she'd take off even faster. So she clearly wasn't really uncomfortable, but the coughing is still concerning. I also noticed when I jumped her over a small fence (about 2'3) she caught her hind legs on it. I didn't think too much of that, but she did the same thing when I rode her today. She never hits anything and we've been schooling 3'3 or so no problem. Its very unusual for her to hit anything, especially multiple times. She coughed maybe 5 times in a 40-50 minute ride, but it was really dusty today. We did some hill work in the field and she felt kinda funny going downhill at the trot. She was fine at the walk and canter, and was totally fine doing on the flat or uphill, but downhill she just felt weird. Not lame, just disjointed almost... She's also been tripping a fair amount lately, but her feet were due to be done (they were trimmed today, so we'll see if the tripping improves tomorrow.)
So to summarize; She's been coughing every 10 minutes or so when I ride, usually while doing heavier work (cantering or jumping) but she did do it once or twice at the walk or the beginning of trotting. She's been moving a little strangely and tripping a lot. She acts perfectly okay otherwise and doesn't seem sick at all, but the coughing is a little concerning since I've never had a single health problem with her in the three years I've owned her. Could it just be allergies? (She's field kept and on tall weeds and crap...) And maybe she's tripping because her feet were long and it's been hot so she isn't paying much attention? I feel like I'm kind of overreacting but I obviously want to get the vet out soon if I think it's anything worth worrying about. Any ideas/opinions?