I wonder if anyone has experienced anything similar or perhaps has any advice.

DD is just on 12 months and is a happy, confident and content little girl.
Two days ago, while playing, she knocked over a folded up chair which fell to the floor with a very loud crash. She looked straight up to her father and I who were standing right nearby - I assumed it was a look, as per usual to check with us for reaction to see whether it was something worth crying about. Usually with something like this where we can see that she has not been physically hurt we will say something to her to assure her that she is ok, ie: acknowledge that she was surprised/hurt/frightened but that she will be ok. Usually she will happily go back to what she was doing or if it is a bit more serious to her, she might begin to cry. If that is the case we will scoop her up and comfort her in a positive way. 9 times out of 10 we don't need to do this as she is a really robust little girl.
This time, however, was one of those 1 out of 10 times and she needed a hug. Fair enough. DH was already on his way over, she was in his arms quick smart and was cuddled. Problem was, she was really upset... and kept crying. DH passed her to me and she was still really upset. Eventually when she stopped crying I realised she had become so worked up she was hyperventilating . It took me a good while to settle her.

I was a bit worried that she had become so upset over a seemingly minor thing, then, today it happened again! Again, after a relatively minor incident (DD hurt herself while playing with a toy) she became upset beyond normal and began hyperventilating again. I was there to settle her once again but I am a bit worried about this pattern. My rational brain tells me that it is probably just a phase while she figures out control of her environement, but my emotional brain is a little worried about these seemingly normal incidents leading to an over the top response and hyperventilation.

Has anyone else experienced this?