Should i be worried about passing out or being super dizzy and vomiting after i try to walk after a months of bed rest?

Well it is expected: well a month of bed rest why were you in coma or did you have a pelvic fracture required so much bed rest first of course in one hand it is expected to have a dizziness and light headed after long bed rest part of it could mean you are still dehydrated part you might be anemic so either way check with your doctor i will worry more about DVT and pulmonary embolism after long rest hope taking asa

Postural hypotension: You should be worried about passing out and vomiting from trying to walk. You are likely experiencing the deconditioning of your bodies' ability to control blood pressure to your brain because of the length of your bed rest . If you stay hydrated and get up a bit more slowly and wait a bit before you start walking this should resolve over time. See your provider if this persists or worsens.