Passing out!

So I'm 12 weeks. Today I wasn't feeling good (not something I could describe exactly what it was I was feelintbg just a vague not feeling good. Everything started going dark & next thing I know I'm waking up on the floor. My blood sugar was fine as I constantly eat and had just had a peanut butter/jelly, my blood pressure was ok (I checked it with the automated one we have from walgreens) and my hr was a little fast but normal for me. Anyone have any other ideas why this would be happening?! I feel overly emotional & just wanna cry. Like more emotional than I feel normal for the situation. I don't know if it's bc I'm just scared and pregnant or if it's hormonal and has something to do with me passing out. Any help or advice please. I'm just scared & home alone w/my other two children & my husbands at work & leaves his phone at his desk. ?