Growth spurts are so, so hard. Fortunately, they only last a few days at a time, then the baby settles again (in prep for the next one, lol). But seriously, you will get through this.
The only other thing I wondered was... do you have a fast let down? If she has increased her feeding and you feel like you're producing more milk, it might be that the milk is coming out so fast that she can't keep up and she is kind of drowning in it. This can scare babies because of the speed, although, they get used to it. I do know that issues with fast let down are common around weeks 4+ when the supply is changing all the time to accommodate your LO.
I have a very fast let down which is why Luke only needs to feed for around 5 minutes per feed but he loves getting massive mouthfuls even if he does come off spluttering and choking on it.
Just a thought anyway.
You're doing well though Dannii and well done for sticking with it. It's so easy to give up and you've not xxxx