Yikes. They are in their most vulnerable stage right now, so obviously the worst time to leave them unattended. I definitely wouldn't want to leave seedlings outside this early in the season - animals are quick to eat young fresh vegetation. I also wouldn't want any container that I planned on flowering inside to be exposed to the pests and insects of the outdoors.
Do you have a friend that can stop by and water them a couple days? That would the safest route for both you, and your plants. Leaving them outdoors is honestly the worst choice. If you can afford it, you could look into a cheap drip system to setup before you leave. Personally, there's no way I'm leaving my babies unattended for 5 days during the crux of their initial development, it's just not good practice.