It is very common for Crohn's patients, especially due to malabsorption in the terminal ileum (end of the small intestine) where vitamin D is absorbed - if you got inflammation, then vitamin D absorption can be severely affected.
Are you sure your GI doctor was prescribing 50,000 IU (that is 50 standard 1,000 IU tabs) per day? Or did you take that over the 4 week period? I am taking 2,000 IU and the FDA tolerance limit for adults is 4,000 IU. On the 50,000 IU level per day, that's what the internet says: "In healthy adults, sustained intake of more than 1250 μg/day (50,000 IU) can produce overt toxicity after several months and can increase serum 25-hydroxyvitamin D levels to 150 ng/ml and greater".
Hope you get diagnosed soon and can then start treatment if you currently got problems.