will it end ? am i normal ? why am i obsessed with these thoughts?

hi guys ,
today is the 6th day or 7th day of my reboot, a while ago my family suggested girls for 2 times to propose to and in both time i felt that i can't complete my life with these girl and before sending my massage of breaking up i find them send massage says the same which makes my conscience calm.

since 2 years and i'm really admired with girl but i didn't told her because her beauty is normal and the beauty standard in my mind is so high actually can't even judge on her physical beauty because sometimes i feel she's the most beautiful girl on the earth and in other time she is normal.

yesterday she confessed for me and i told her that i'm not stable emotionally because i have an OCD therefore i can't give her the sure exact decision currently i need at least 2 or 3 months maximum to complete my plan (actually to complete reboot ) she told me to go to psychiatrist ,so i told her that i'll do it even if i couldn't pass this 3 months (actually that's what i'm planning to do ) but for sure i told her only about the OCD not about PMO but i'm fighting both because both are strongly related with me. actually i was planning to go to her after the 3 months but she also did it before me .

my problem is
she is shorter than me i'm not sure how short she is but i think she is shorter than i like because i wanted a girl who's shorter than me but not to that extent, although i'm not sure how short she is . so i started to have strong intense thoughts about the she won't be good in bed although i read many topics says there's no big difference because most or all sexual positions can be change for a tall or short girl but i still have these thoughts ,and the worst when i see a girl in my height or slightly shorter than me i start to think the her height isn't good and start to think about certain thing which is i won't be able to kiss her while intercourse (in the same time) , and start to think to have sex with the girl whom I've seen if they were in my height or slightly shorter than me although i deal normally with these girls and i may didn't think about these girls before, but mind is thinking about that, and she won't be good, and this makes me hating myself more than i do . and i didn't pay attention for her height because i didn't think about something like that before. and i didn't find an answer for the main problematic idea above .

i feel i really love her and when i'm with her i feel so comfortable and happy actually i feel that i don't wanna go home and my obsession with her increased after her confession , but i don't know why such thoughts coming into my mind and i consider thinking about other girls as betraying for her true feelings regardless i hate it and i hate myself when i think about something like that ,so the feeling of betraying add more load on me .

note : we are in community believe in chastity ,so we can't ever think about sex outside the marriage actually when she told me her feeling she did in indirect way but i could force her to do it explicitly because i don't want to build everything on illusions and guesses .

my questions
1- why do i have these thoughts ,is it because of my OCD and being in the 6th day of reboot ?
2- will these bad intense thoughts as i go in reboot ?
3- although i told her that i can't take any decision currently because of my situation and she told me that she understand , i'm still having an unexplained anxiety ?
4- why do i always think about my sexual relationship will be bad or will fail, is it because of my OCD and OMP?
5- i hate myself ! for my OCD and for my PMO because i can't focus on the feeling of love instead think about something like this (kissing during sexual intercourse)

thank you in advance if i couldn't replay in time