Pregnant or just sick

I had sex on the 11th ( we used a condom and I am on the pill he did cum into the comdom in me though) and last night (13th) I had diarrhea, nausea, and stomach aches and now today the (14th) I woke up and I still felt this way. The stomach aches feels like the pain you would have after doing ab work outs / overeating. There is a stomach virus going around tho but Could I be pregnant or just sick?