I probably goofed big time , but I thought I'd see if anyone here has any advice which could help.

In planning a recent trip to the caribbean, I noticed that the flight from San Juan (SJU) to my destination that fit my schedule had only a couple of seats left on it, so I panicked and bought THIS ticket first (on LIAT) directly through LIAT's website. The next day I completed my travel planning by buying the rest of my tickets to get down to SJU and back from where I live (These tix are on USAirways) through expedia. All good until yesterday when I reconfirmed the schedules for LIAT. They have now added another stop on the schedule for the return flight , and it seems I will now misconnect on my return flight from SJU to my home airport!

Since I bought these tix on two different websites, am I SOL? I will definately need to do something, but where do I start and what can I expect (pay $$ in fees, etc)? Expedia, USAir, LIAT? Any advice to lessen the pain would be really appreciated!

Thanks!