Pain near anal region. Get night mares!

Hello Doctor, I have pain near left side of the anal region. When Im about to pass stool and when the anal region gets opened I get a slight pain as if it has been cut or torn.The rest happens smoothly.It hurts only on the left side and sometimes the pain stays there for half of the day.this anal problem has been with me frm past 10years and now I get so damn scared thinking about the pain and even get night mares regarding this.Is this pain can be a result of my overthinking about the same problm everyday.can pyschologyical issues can result in reoccurrence of this pain in anal region?I'm damn scared to get the test done and also surgery.not sure how to go about it.From past 10years this has been a recurring problem but not continuos.When first doctor diagnosed he said I have got internal piles and then after few months due to lack of diet I had to suffer from fissures. After that I naturally cured it by taking healthy diet but the problem is not getting over. is there a perm solution