Ok being and IBS sufferer myself I understand that we need to know wht pain is normal and what isnt normal for us individually.
When I get new symptoms and symptoms that seem to be unusual for me I always make sure I tell my GP about them as this will keep you safe from anything that could be happening. Letting them know is very important.

However if the pain ever gets really bad, worse than you ever had it then I would advise to go to your GP again and please mentiion to them that you think it could be diverticulitis. my mum had this and nearly ended up in hospital it can be serious if not treated. She had two weeks of strong antibiotics and has come right.

But all Im saying is please get it checked if it does not seem normal to you or if the pain is worse than normal especially if its lasting longer than normal too.