GI thinks fissure but PCP thinks crohns.

I am seeing a colon rectal surgeon for a second opinion. My symptoms are as follows. Sharp rectal pain that comes and goes, having to strain to have a bowel movement but soft, false urges, bright red blood sometimes and urgency.
GI thinks fissure without any type of exam but PCP thinks crohns spread to rectum, after explaining this to GI and he asked me more questions he said I think it is the crohns but didn't do any exam.
I am on Humaria, when I miss a dose I do get serious rectal symptoms, rectum feels like on fire, urgency, increased frequency, left lower abdominal pain but all this goes away 2 days after humaria injection.
I have decided to get a second opinion from a colon dr because I don't want this to get out of control but humaria not helping so afriad something else.

Question: Very nervous never saw this type of doctor before. What ca I expect at the appointment.

Thank you