dysregulated child

hello all 

I am new to this group and I am looking for ways to support my daughter who is 7 years old and really struggles with becoming dysregulated very quickly and very easily on a daily basis.

Things that trigger her seem to be everything. And by this I mean changing tasks, going to places such as school and anything that cause her to have a change in emotions. When she is dysregulated she is very aggressive and takes her anger out on whoever is around her physically and whatever she can get her hands on she will destroy if given the chance.

I have brought her a sensory sock which helps in the cooler months but she is very sensitive to temperature and in this current heat getting her to go in the sensory sock makes her more distressed. I try to make sure she has fidget toys where ever possible but we are yet to find one which she has clicked with for more than a few days.

When she is in a state of dysregulation it can be very hard to get through to her with her often becoming non verbal and only screaming as a way of communicating. Currently the only thing that seems to calm her down is letting her go on her tablet to watch youtube but I feel like I am rewarding the 'negative' behaviour by letting her have her tablet when she is in this state. I understand I need to change my mindset around this and I am working on that as best as I can but I am struggling. 

Any tips or tricks welcome as I'm struggling and feel like I am failing her when she is unhappy and unsettled.