Most traumatic experience

so hi,
Honestly, I have just registered and don’t even know if my story fits into PTSD… But i really need to talk about this thing that happened to me on Monday…
So I’ll just start.
I am 19 years old and still going to university but it is still summer break, so i spent the last few weeks at my boyfriends house. His parents weren’t at home, as they are on vacation. We are doing long distance, so it was a nice experience to ‘live alone’ just like a normal couple does.
everything was going really well until Monday morning… It was around 07:05 in the morning. My boyfriend was already awake because he had to go to work, just like every other day. He was brushing his teeth, when the door bell rang. From this moment, I was wide awake, because deep down I knew that something was wrong. Next to him lives an elderly couple and on the right side is a house, that is getting renovated, so no one is living there.
As always, the front door was locked and he came into his room to get the keys. He just said “It’s my neighbour, I have to help her”. Well I thought he meant the elderly couple, as it is not uncommon that they might have some health problems.
I changed my clothes and went to the front door. When I got out of the door i could see smoke coming out of the garage next to his house ( the house that is getting renovated) and a woman was screaming and crying so so loud. the first thought that came into my head was that the garage might be on fire. But the woman was screaming something about a child, so my next thought was, that she locked herself out of the car and her child is still in it while the engine was running.
She told my boyfriend to call an ambulance and it took quite some time until it arrived. You have to imagine that I still did not know what was going on.
standing on the front door and waiting made me go insane. When the ambulance arrived, Until late afternoon, I thought that it wouldn’t impact me that much, but clearly i was wrong. I started crying really bad and was afraid to go to sleep. I am an extremely sensitive person but my mind keeps telling me that my boyfriend has it a lot worse than I do ( he is not that sensitive, but still he saw him and i did not). A few days have gone by and we do not talk about it that much, because i do not know how he deals with it. You see it might be easier for him, if i don’t bring it up that often. Since Monday, i am really afraid of the dark and being alone. As soon as evening and night arrive, I constantly thing about it if i do not have a distraction. When I lay in bed trying to sleep, my mind keeps me awake. I have to watch videos on my iPad and fall asleep while watching, otherwise I will think about it and wont be able to sleep. I haven’t had nightmares but it still has left its marks on me.
I left Tuesday morning as i had already booked my ticket weeks in advance. In a weird way, i was happy to be at home. He is currently sleeping at his friends house until his parents come back on Saturday.

Do you have any recommendations on how to deal with the situation?
(Sorry, if there are typos or something… English isn’t my first language..)

I'm sorry you've had such a troubling experience ...

I think it's important for you see a counselor to help you process the event.

Many Universities offer free or low cost counseling services for students.

If yours does not, then perhaps there's other counseling options available near your school.

Check into that and keep us posted on how you're doing.