Welcome to the community @JESS2, you’ve been so brave to share your story here with us all. What you’re going through is not easy to talk about and I really admire the strength you’ve shown reaching out.
I’m really sorry to hear about your Dad and Grandad passing away. I can hear how close you were to your Dad, you mentioned he was like a best friend to you. From what you’ve shared, it sounds traumatic not knowing how long you had left with him and getting the call not longer after you last saw him. It’s understandable to hear phone calls late at night are triggering for you, I can imagine it bring up lots of difficult feelings. It sounds like not being with him that last night is something that’s on your mind a lot, is that right?
I wanted to link you to a few other topics on the community from a few other young people who have experienced losing their parent who you may like to connect with - Losing a Parent Whilst in Your 20s and also My dad passed away and I’m only young.
There’s also this post here which you may like to read:
Keep posting here whenever you need to, we’re all here for you 