I accidentally ate unpasteurized soft cheese (from a cheese plate) while 15 weeks pregnant. does cheese like this always have lysteria? what are the actual chances/statistics that it does and i might be infected? how worried should i be?

It rarely contains Listeria. Ask if anyone at party got sick. Go to CDC.gov for more info. Usually a classic Mexican cheese whose name I cannot recall now.

There is a real risk here but impossible to place a number on that - all you can do is be vigilant and look for signs of illness related to food borne illness- bloating, diarrhea, malaise, muscle aches, fever, if severe infection, headache, neck stiffness, lethargy, and convulsions… the incubation is long, if you have no S/S of food poisoning or fever, you are OK if a month passes and no symptoms