Just saw your post and hope you skipped the shot because 83 is too low to shoot. I am not very familiar with your insulin but I do know it acts faster than some others and could drop his sugar levels even more and rather quickly. Rule of thumb...don't shoot under 200.
In a situation like this , I'd feed Magellan and check his BG again about an hour later and then based on that reading you can decide what to do. 83 is actually a really nice number but it's not high enough to give him insulin.