Sneezing. She'll very likely just have a tickly hair up there, they spend a lot of time sniffing things and the membranes are very sensitive. Mine sneeze regularly and often violently, it's not a worry.
Good work with the training, don't overdo it, 10 mins at a time is more than enough for the smart cookies like terriers, then they start to get bored or do it wrong. Mimi was bad for recall for ages, too easily distracted or choosing to ignore me. Myself and the good lady take a handful of treats out occasionally and separate by a good distance. One calls, she runs and gets the treat and praise, then the other of us does the same. Lots of exercise and positive feedback for the dog, she loves it.
House training was a pain though. We got her at about 12 weeks and she had no idea about it at all. The pads and paper were great fun toys, so we had to stop with the pads because of the absorbent crystals in them. I'd get her up every couple of hours or so at night and take her to the garden and watch her with a torch. This was late September 2014, windy, wet, Autumn leaves skittering across the lawn like live things that needed chasing. That was hard work because she didn't really know what she was outside for, but when she went, lots of praise and strokes.
Eventually, on a trainers advice, we taught her to ring a bell. Sounds mad, but it's really easy. Parrot type bell hanging from hand that also holds tasty stuff. Chicken is great for this. She wants the chicken so paws at your hand which makes the bell ring. Very quickly give the treat and put her straight into the garden. She'll soon began to associate ringing the bell gets her outside. If she does a wee or poo, then lots of praise but no further chicken. It's really handy in the night, or when you haven't noticed the dog slipping out of the room.