Sleeping with mouth slightly open??

[discojan]

Tonight, our big girl fell asleep with her mouth slightly open. It's about 70 in her viv, so it's definitely not too hot. Is this a normal thing or something we should be worried about? (She has never done it before--it's not a full gape, just a little cracked open). She is pooping and eating regularly, and is actually getting kind of big. She is 3.5 years old, and she eats mostly greens(Collard/mustard/turnip with occasional black or blue berry, squash, pumpkin, other treats now and then) and a few butterworms (10-15) or 1 -2 hornworms a week, but she is 50 grams heavier now than when we adopted her in August. She is 21.5 inches and hovering around 700 g; she used to weight 647g. Could the extra weight make it harder for her to breathe? As soon as it warms up outside, we plan to let her 'water jog/swim' in a kiddie pool to help her get more exercise.