How do I get back to where I was?

justkeepswimming717

Hey, guys! So I just joined today... And I don't know how to start.
A little bit about me: I've been a swimmer since I was 4, and I recently stopped my rigorous 4-hours-a-day workouts because of the lack of time I have in my life to keep this up. It's been 2 months, and I've gained almost 10 lbs, as well as some of the muscle I'd worked so hard for. I'm 5'3", 18 years old, female, and very, very small framed. I used to be 105 and now I'm 115.
Does anyone have any good ideas on how to get started? I want to lose the 10 lbs I've gained, and get back into perfect shape again as quickly as I can. I also want to shake the bad eating habits I gained after quitting swimming. I used to eat so healthily, with just the right amount for my body, and now I find myself eating unhealthy amounts of unhealthy things. :embarassed: