I'm sorry you're going through this. However, there is definitely hope.
This is a great website and hopefully can help with some of the immediate scrupulosity stuff: https://scrupulousanonymous.org/
Ask your parish priest or the diocese if there is a list of spiritual advisors and/or if the priest would be willing to hear your confession once a week for a set amount of time (like 15 minutes). Having a spiritual counselor or dedicated confessor really helps get you out of your own head. Tell them that you are struggling with scrupulosity. It's possible that they've either dealt with it personally or know someone who has.
There are online therapists available, like at NOCD: https://www.treatmyocd.com/. Do a bit of googling and see if you have access to telehealth mental health care. There are also workbooks you can order. I personally liked The OCD Workbook: https://www.amazon.com/OCD-Workbook-Breaking-Obsessive-Compulsive-Disorder-ebook/dp/B004G5Z7BM.
So here is the first thing, it's totally reasonable to feel guilt and pain for doing things that you feel were hurtful. It's important to use these feelings to do better. All of this is I'm writing is really focusing on the obsessive checking, rumination and compulsions. Doing these things are pretty much lighting your brain on fire and pushing you deeper and deeper down a dark OCD hole. Reaching out to something like NOCD would be 10x more helpful, but if you can start to do anything on this routine I think you'd start to feel better.
Here is a daily routine I did when I was feeling terrible.
5-10 mins meditation. I use an app. I like Waking Up, but any of them are fine. The key to meditation for OCD is learning how to let thoughts go. Even when you're feeling better, you're going to have crazy thoughts from time to time. Meditation helps you let them go and not ruminate. With this version of OCD, rumination is our number 1 compulsion, we have to stop but its so hard.
5-10 mins ERP. This is the book I would read to start to understand The OCD Workbook I don't know how comfortable you are on starting ERP on your own, but I do think it's a huge huge part in getting better. I do a script, I write out my worst fears and just follow it to the end. It will feel absolutely terrible. Sit in that terrible feeling, try not to ruminate. Accept the uncertainty/possibility. Sit in that feeling until the anxiety subsides. I built my ERP program using this book I also dialed it in a bit more using NOCD.
30 mins of exercise while listening to an OCD podcast. You're going to feel terrible, so it's really good to get outside a feel better. Walk, run, go to the gym. Whatever. I like doing it right after ERP. I think it helps. I'd start with listening to The OCD Stories Podcast. Hearing other peoples struggles and solutions is huge.
https://www.fearcastpodcast.com/2020/07/14/real-event-ocd/
https://theocdstories.com/podcast/stacey-kuhl-wochner-real-event-ocd/
30 mins minimum of OCD reading. I think reading about OCD is huge, unless you go to a specialist. Most therapists are not even that well versed in the disorder. Here are the first 3 I would start with. PM me for any more recommendations. If you feel yourself unable to get out of a rumination cycle, pick up the book and read. I've been finding book on stoicism and Buddhism to help as well.
Freedom from Obsessive Compulsive Disorder
Everyday Mindfulness for OCD
Overcoming Unwanted Intrusive Thoughts
No, porn can't "change" your sexual orientation. Watching porn can be a compulsion and way of reassuring yourself, which will just make your OCD and anxiety worse, so I suggest staying away from it. If it helps, download and install software that keeps you away from it. What you need to do is Exposure Response Prevention (ERP). So you have the thought "I'm gay (or lesbian, or bi or whatever)". Now, you need to say it over and over until you get used to it. Maybe you're gay and maybe you're not. Part of recovering from HOCD is dealing with the uncertainty. If that sounds too hard, start with the statement "In Egypt, there was a young man (I'm assuming you're a guy?) who thought he might be gay." four times each, four times a day and bring it closer and closer--next might be Africa, Mexico, France, etc., until it's eventually where you live. It helps to have a therapist, but you can do ERP on your own. I have a workbook, "The OCD Workbook: third edition: Your Guide to Breaking Free From Obsessive Compulsive Disorder" by Bruce M. Hyman, Ph.D., and Cherry Pedrick, RN. It's really good and helps a lot. You can buy the book on Amazon, and it will be the best $15 you ever spent: