Some need assurance. But constantly asking the same question is not advisable. Please be advised that your primary doctor who you consulted is more than competent and you did follow his advice...

If its not painful then u can wash with finger. Fissure usually will not turn into abscess. If u have any issues in future Always get examined by a surgeon

There is nothing to panic about. No extra cleaning technique is required. Continue regular washing plus sitz Bath after passing stools which will help prevent infection and also relieves pain to certain extent. If you see any white discharge from the anal opening, fever, increase in pain, then it can be due to pus formation and immediate treatment is required.

I tried answering the same question thrice .You have anxiety disorder .Consult a psychiatrist.