Positive ANA

I saw my dermatologist and asked him about the difference between a lupus butterfly rash and rosacea because I get a sunburn-like rash off and on that lasts for several hours or sometimes a day then goes away that looks like the butterfly rash of lupus.  I also have had sacroiliitis recently and have had problems with headaches since I was 12.  I know my grandma had "sick headaches" a lot (she had lupus) and I saw her butterfly rash also as a child.  He said that rosacea usually would have bumps too (which mine does not).  He sent me to the lab for what he said was lupus testing.  On the lab sheet was marked ANA and Sjogren's as tests to be drawn.  His nurse called and said everything was negative except for the ANA.  I asked if she knew the specific numbers, and she said it was only negative or positive.  She got him on the phone and he said since all the other things were negative he didn't think this was lupus.  I want to just accept his opinion and be relieved, but I just have this nagging feeling I should look further into it.  I have a recent diagnosis of Crohn's disease and was recently in the hospital.  My spleen was enlarged on abdominal ultrasound and my surgeon suggested I be tested for autoimmune diseases especially lupus.  Could the Crohn's cause it to be positive even though it is under control now? Anyone have advice for me? Thanks in advance!!