I can't answer this thoroughly yet, but will re-read through it later when I get a chance, but..
Blowing bubbles in the water, happens with Ball Pythons. That's not to say every one does it, but its known to happen, and there aren't usually any issues associated with it. Just one of those goofy things they tend to do at times.
Constant yawning can be indicative of a respiratory infection or disorder. However again, they are known to yawn from time to time. if she isn't displaying any other symptoms of an RI (wheezing, mucous around the snout or mouth) ect. I wouldn't jump to conclusions or stress over it yet.
In regards to the head photos, I didn't see anything super alarming. But there does appear to be an old injury, scrape, or bad prior shed going on there. But it looks healed.
I'd also probably be offering her 2 F/T fuzzies. Just make sure the first is down before you offer the second. That seems like an awful small meal.