Could it be menstrual migraine? I have suffered from complicated migraines for years, but also have monthly migraines associated with my cycle. I believe they are fairly common.
Dizziness is often connected with migraines as an aura or as an after effect. It is also a normal effect of a migraine to feel generally unwell afterward.
Just because they are common doesn't mean that they aren't horrible!
If you are like most, then your uc probably acts up during your period, so who needs one more painful affliction!
You should think about seeing a doctor . There are quite a few meds. Alot can be taken by people with IBD, but they all come with there own set of side effects.
I take Topamax to help prevent migraines, but when i get one, I still take advil and use a heating pad which of course, most with IBD cannot do.