My anus sometimes itch... Help me solve my problem

I am 18 years old boy, with normal weight and with problem with anal region. In a past period my anus began itching. The first moment was probably when i drank too much coffee. (I think it was). I didn't really recognized it, but I think the problem was with the coffee. I found a little bit fresh coloured blood on paper, after the stool 2/3 in past lets say 4/5 months.. I went to a doctor, he didn't ask me to get naked, but he gave me a 'Factu' cream for haemorrhoids and anal fissures. I don't have any cramps or any problems with stomach pain or something similar. He was assuming that that was a problem. He took my stool and test it on a parasites. It was clear. In last period sometimes I feel my urinary track is also in a little bit problem. Sometimes its uncomfortable to sit in some position, but I don't have problem with urinating and other stuff. When I told him that, he said that it could be because of the haemorrhoids. I stopped drinking coffee, and it helped a lot. I think cream helped me too. I did have unprotected sex just once and that was 2 years ago. I don't have any other symptoms except anal itch and maybe something i described with urinary tract. I am worried because I took photo of my anus and it seems like a little bit red-ish? I also do have a little problem with psoriasis on my knees and elbows. He also told me that I need to change my diet etc. Here's a picture. I don't know, it's maybe the picture that shows a little bit purple and red colour. But I think it's fine in person. I am worried, but I do think I am overreacting sometimes. Please help me...

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