Confused about a few peptic things

Four years ago I was deathly ill and in the ICU for five weeks.  During that time I had over 20 CT scans.  When I was discharged I was told there would be side effects from all the radiation.  Seven months ago I was diagnosed with 8 small bleeding ulcers and erosion in my esophagus.  They tested for H-pylori and it was negative.  They blamed it on NSAIDSs, which is a legitimate reason.  I just can't help but wonder though if it did have something to do with all that radiation.  Could it have perhaps weakened the lining of my stomach, making it more vulnerable to the NSAIDs?  Also, since I was diagnosed with the ulcers I completely changed my lifestyle.  I quit smoking.  I eat a balanced diet now.  I don't take any NSAIDs.  I don't eat tomatoes, citrus, chocolate, or partake in any form of caffine.  I completely quit coffee and soda.  I don't even drink tea anymore.  I try to eat three small meals and three small snacks a day.  I do everything I'm supposed to and more I think.  The way I live is really quite annoying.  When I last went to the doctor to check up and see how I'm progressing (this was a couple weeks ago), the doctor told me they don't run another scope unless I'm still having symptoms while on the nexium.  For the most part I was not.  The doctor told me to quit taking the nexium for a couple of days(2-5) and see how it went.  He said if I was having discomfort to just take the nexium.  The first day I stopped it I had severe stomach pains.  Like I was being poked from the inside with a knitting needle.  After that, there was a period of about seven days when I didn't take the nexium and I didn't really have any problems, only a few minor pokey feelings here and there, but nothing so severe that i reached for the nexium.  About a week ago though my stomach started bothering me again.  It's a terrible burning, gnawing, poking feeling from right below my belly button all the way to right under my breasts and it isn't limited to sides.  It is all over.  I have been taking my nexium again now and I don't wait till it starts hurting to take it either, but it has still been hurting and giving me severe discomfort.  The doctor had said that if I was having symptoms even while taking the nexium that I should make an appointment with him.  Should I make the appointment or is it just doing this because I was off of the nexium for a while?  Is it going to go back to the way it was before I stopped taking the nexium?  He also told me that they don't do a lower GI or colonoscopy unless one of my parents has or had colon cancer in their 30's.  Is that true or do I need to get a second opinion?  Both of my great grand fathers had colon cancer.  I did tell him I recently saw a significant amount of blood in my stool and he said it was probably just hemorrhoids.  He didn't check me for them though, and he also didn't ask me how bright or dark the blood was.  He also didn't ask if it was mixed in with the stool or not.  I have done a lot of research on this stuff, and I felt like when I went to that appointment that doctor treated me like I was stupid.  He kept telling me not to have caffine or take NSAIDs or anything like that.  I don't know everything about Gastroenterology, but I know at least the basics about ulcers.  I think after seven months of having been diagnosed with ulcers anybody would know a thing or two about it.  There is such a thing as the internet.  Please help me.  I'm so confused about what to do now, and about whether the CT scans had anything to do with this.