If you can do that many sessions a week you'll breeze a sprint. I'm not sure how good your swimming or cycling is, but I reckon you'll soon be eyeing up the longer events! Very sensible to start with a sprint first though.
My best advice would be to combine one of your bike sessions with a run, so that you can not only practice transitions ( vital at this distance where you can easily make up a heap of time on a much better swimmer, by having an efficient transition), but also to get used to that fantastic feeling of running off the bike.
Enjoy your training mate!