Is it HOCD or am I just in denial?

I've posted before about this but basically my head is just so messed up right now. I'm a girl, 18 years old and I keep thinking I'm becoming a lesbian. The thoughts are intrusive and not constant and make me feel scared and worried. I've had countless panic attacks about them. I have an obsessive nature and I have suffered intrusive obsessive thoughts in the past about typical OCD things. I know I shouldn’t be searching for proof and searching the internet for relief and help but I need to. Just give me your opinions and I’ll to write everything as honestly as possible. Here goes.

I've always liked boys and currently have a crush on a boy and a male teacher in my school. They make me happy and my heart starts to flutter and my stomach drops when I’m around them. With the teacher it's a bit more of a fan crush because he's about 7 years older than me and so my feelings are more physical because he is honestly gorgeous and can’t be around him for long periods of time or I’ll start to smile like and idiot. But with the boy it's different. I want to be around him, to have his attention only on me. I know deep down I've never felt that way about a girl before. But my head still tells me if I think a girl is pretty then I'm a lesbian. The only girls I've ever been like wow are usually celebrities, those models who I want to look like or be like and have the clothes of. I've never had a sexual attraction, or if I did it doesn’t come to mind right away. I could list the boys I’ve liked and I have been jealous of girls for being pretty but I never wanted to be WITH them or at least I don’t think I did. I wanted to BE them or be their best friend because with that came a reputation and with that came boys…

But, I can have abandonment issues and can get slightly possessive of my friends. If my best friend starts to get to know someone I don't like then I feel annoyed and I want my friend all to myself. This has caused me a lot of anxiety and worry because I interpret this as a lesbian crush. I like being in the company of my friends, of course I do they're my friends and I revel in the attention of boys. But the terrifying thought returns. I posted a question on this about a month and half ago on the same topic and shortly after that, from the responses I received, my worry completely disappeared. I was back to obsessing over my teacher and crushing on my friend, but now it's back and the fact that it isn’t a constant thing doesn’t change what it’s telling me; You’re a lesbian, it’s so obvious. That’s why this happened or that never happened. That only happens to lesbians, you dress like a lesbian. Wear that top so everyone will know you’re a lesbian. Yes, it’s gone so far that I don’t wear certain clothes for fear that someone will think I’m a lesbian.

I have all the signs and symptoms, I obsessively think, my compulsions help me, relax me and then I get over it. But something will trigger another attack and I’ll freak again and then fall into the depression that always comes after and then I’ll try to reassure myself again. This cycle has started again. I know I’m straight and that little voice within me always comes up and reminds me that I’ve never felt that way about a girl before. But no, it’s not strong enough.
Even writing this is somehow reassuring me that I’m not a lesbian… When I think it may be OCD it relaxes me, but then a thought comes on, ‘Yeah, it could be HOCD and you could be worrying and panicking about nothing OR you could just be a closeted lesbian in denial who so happens to have OCD as well.’
I’m 18 so I’m pretty sure puberty is gone. I don’t have the excuse of mental hormones to relax me. What is it? Someone help me because I’m scaring myself with this. I’m not going to lie, there was a fleeting thought of suicide… buts that gone. I couldn’t do that to my family. It’s just; I want to be with a man. They’re strong and beautiful and smell amazing but I can’t deal with that thought when there are about twenty others saying that I can’t have that and make me avoid my friends in case I start seeing them as sexually attractive. Anyway thanks for reading this if you did, I just needed to vent.

Harm ocd is scary I'm thinking about going to a mental hospital because of my "harm-ocd"