I'm pregnant and have food poisoning, should I go to the hospital?

No. Although food poisoning can be miserable in general it will not hurt the fetus. Most cases can be managed at home and resolve in 24-48 hours. The key is to avoid dehydration. If you develop fever, have bloody diarrhea, have contractions or can not stay hydrated then yes you should be seen in the hospital.
Yes. Absolutely - better safe than sorry! what may seem normal could develop into something worse. Be proactive and stay on top of potential risks.
Yes. Absolutely, call your OB or go to the hospital if you truly believe it is food poisoning. Certain organisms will not cure themselves with time, but only with antibiotics. Also dehydration must be avoided at all cost.