I Reside In Florida, Where Red Tide Is Terrible.it Has

I reside in Florida, where red tide is terrible.it has caused many people to be ill, but up until now, I have not been affected. Well, last Sunday, I had dinner in a beachfront restaurant(enclosed), and still was impervious to any smell. I who hardly ever dines out, creature of habit(eating my own food, at home) decided to try sushi and sashimi, along with swordfish, and various other varieties of food. My digestive system is not use to this, (lactose intolerant, IBS).. I have had sever diarrhea, and severe nausea since then. Please tell me if this is signs of food poising and how long it lasts. I have drank bottles of malanga, and Pepcid ac..does not work.