Food poisoning is when a certain toxin or virus invades the gut and causes the system to remove all of its contents. It does not cause vertigo. However, the desire to vomit is present because of the guts need to evacuate its contents.
If food poisoning has resulted in loss of fluid, it can cause disorientation and dizziness; however, this is not a direct effect of food poisoning. Instead, it is the effect of low volume in the body. Moreover, constant vomiting after food poisoning is not dangerous unless it persists for more than 2-3 days. At this point, it can become serious due to extreme loss of fluid and needs supportive therapy.