Oh.my.goodness. WTBH, my heart is breaking for you and the girls tonight. This is terrifying. Ok, you're right, you need more stable support than just your mom, who *is* wonderful about giving you the refuge for now, not so much the 9-1-1 situation. Oh well. That was then, this is now.
Now, I do believe you'll get your best support from a domestic violence center. Filing the protective order is the very minimum...there should be some other steps the professionals can help you put in place to immediately feel safer.
A Safe Mommy is a Happy Mommy and an Equipped Mommy to raise these children!
Yes, you will need a good attorney as well. When you meet with your attorney, please take your journal of all the episodes you have, in addition to the dates/times of previous arrests, incidents your AH has been involved in. You will also need all his information from his employer, his SSN, DOB, family information, etc. to turn into your attorney so they may develop a way to serve him when it's time.
You have been doing great in these past few months. This was not something a 'normal' person could have seen coming. But now, you have a glimpse of the progression and now you know all it will do is progress. Thank goodness you're in a safe place tonight!