Insurance. Do you know about it?

I've been advised to get some travel insurance. Seems reasonable. (and by that I mean, seems unreasonable, but it seems like the kind of thing I ought to think is reasonable.)

I guess I'll also need some health insurance for 3 months, because I turn 26 (and thus am off my mom's health plan) in May, and don't start grad school (where presumably I could get on the university's plan) until August.

Here's the thing. Travel insurance covers crazy emergency illnesses, loss of limbs, repatriation of remains*, etc. That's the only thing I'm worried about anyway- if I get a tummyache I'll deal with it myself. Could I get by with just travel insurance until August? Or does that mean I'm "off the rails", there's a gap in my Official American Health Insurance Coverage, and things get difficult or expensive when I try to sign up again?

* This means "if you die we fly your body back home". Why is this such a big deal? If I die, bury me wherever I am! Geez.