Work travel opportunity

So I was just offered an opportunity to take a short trip to Mexico for work. It would be a really cool opportunity to learn some skills that I could bring back to my current job, give me some exposure, and potentially help me advance my career.  Its a short 5 day trip, I've even been offered that I can plan my flights so that I can meet with another member of the trip before we fly out of the country, and someone else would take care of all my travel plans. My husband is encouraging me to go and its Mexico in February vs the bitter cold of New England.... but I'm pretty much turning into a nervous basket case just thinking about it. The day my boss mentioned it to me I had a nightmare that a plane crashed next to my house the same night and I haven't slept well since... and I haven't even committed myself to going (although I'm getting to that now or never time).  I wake up every morning in a panic and have to talk myself down. I've been on trips for a couple of days here and there just on the east coast, so this would be the longest, furthest from home, and first ever out of the country for work (and 2nd ever out of the country period besides driving into Canada). I'm really tense about it and not sure what to do. Any advice?