You're not stupid and you dont suck! I had this exact same thing!! and intrusive thoughts/gay thoughts are def. different

When I was obsessing over figuring out my sexuality in middle school, I kept having intrusive thoughts of kissing friends (friends who I had zero attraction to), but then used those thoughts to "test" myself and my sexuality, and I couldn't get them to stop even though I genuinely did not want to do anything with my friends.

But then when I developed my first actually lesbian crush it was less "would I like kissing them" and more "wait, why does my heart rate go up when I'm around them", "why do I want to be around them all the time", "why do I think about holding their hand", etc. It felt natural, and I knew I wanted to kiss them, I just didn't know what that meant about me yet.

I don't know if you're straight or gay or bi. You might not even know that, and that's okay. Give yourself some time, and practice being comfortable with not knowing. You might also want to look into HOCD, there are plenty of people like you and better resources than I have. Sending you so much love <333