I think I just got PTSD from my job today. Startled at every noise. And there's more. I feel like I'm FUBAR?

So some total stranger passerby stopped tonight as I was walking to my car and said he wanted to make sure I was okay because I looked "pissed off" when I was trying to avoid not looking pissed off. (I have really bad facial tics when I am insecure.) I am crazy, but I'm tired of people giving me funky looks and them treating like I'm homicidal or have Asperger's or something. I never want to hurt someone, and when I feel like I have hurt someone, I almost always have this guilty conscience that eats me up. It's like I can't go anywhere in public without feeling like everyone is looking at me and judging me. The stranger asked, and I told him what had happened, and he started walking away and he just said "You got it. I have faith in you." I don't have it. I loved my job up until now. I have been taking care of this lady who has had 6 seizures since February while I was taking care of her. The first 3 before today were no big deal. The ones today were scary. She usually screams "HELP ME" before she has one, and I rush to help her. The first one today she was eating and had food in her mouth, and I thought she would choke. The second one was scarier. Her seizure lasted 4 minutes and she was confused for way too long (8 min) and her family and I didn't know if she was coming back or not. Then when I was filling out the report about 15 minutes after the bad one where she started seizing before she said "help," I thought we were going to lose her and she didn't come out of the confusion for 15 minutes. All these were all in a less than 2 hour timeframe. After her last one, she just coughed or something, and I got startled and thought she'd have another one. Then her family and I talked outside, and I thought I heard her scream, I panicked and told him I thought she was having another. On my way home, I got 2 minor startle responses when driving. Thought I was going to hit a pedestrian and then I thought someone was going to run into me when most people wouldn't think that. I have a therapist, but I'm afraid of everything. I don't know if I can work anymore. I'm so afraid she might die. And I start to feel angry 6 hours into my shift at the one where I sit there and do nothing important and I feel like I will blow up/lose control. As far as I know, everyone wants me to stay at my caretaker job. Boss is impressed/surprised. Family does not want me to leave. The lady I take care of seems to really care about me, and she gets sad when I tell her I can't be there forever. I don't feel like going anywhere. I don't even like going out to eat anymore because people always look at me weird. Everything stresses me out. I have really bad anxiety, but now I'm afraid I might have PTSD, and I don't know what I can do if anything. I was going to nursing school, but I'm so terrified I might accidentally not do my job right and someone will die because of it and I'll have all the incidents replaying in my mind where I could have saved someone. And I have to deal with me ex bf trying to convince me I'm the greatest person in the world and that he really does care while calling me an asshole who overanalyzes and freaks out way too much. 8 calls between 3am and 10am while my phone was on silent and then him saying I was breaking my promises and leaving him. "Fine" trying to convince himself. He tells me to "GO AWAY! Forever!" and then 15 minutes later texts back with "Hello, C******??" If you're curious, see my last Yahoo question. I don't know who to share things with. People are running away from me it seems, especially after tonight. I feel like my stomach is up between my sternum and my heart has a hole in it. I have these terrible sexual thoughts, and my ex has been trying to claim the right to my entire body just because we ****** (he's territorial like this with all his exes he's had feelings for. Even pissed one of his ex's carpet when he came over and found another man in her presence.) I have to have some kind of sexual release to feel normal. I don't feel like I can orgasm anymore. I want to sleep with someone but am so afraid that I'll get treated like **** by my ex and whoever I decide to sleep with, and they might be the best friend I have, and I don't want to **** things up. I feel totally ****** up out of my mind and all I want to do is curl into a ball and never wake up.