Nerves=upset stomach?

So I'm supposed to be leaving for a day trip with my boyfriend in an hour or so, and I kinda have an upset stomach. I'm really nervous, and I've been nervous since last night. I don't necessarily feel sick but I have a bit of loose poop (tmi, sorry) and I'm slightly nauseous. I took a pepto bismol but I'm still worried because I'd be so embarrassed if I got sick or had to go to the bathroom while I was with him. Can anxiety make your stomach upset like this? :(