if you swim every morning you're in better shape than 90% of the people out there I guarantee that.
I swam some laps earlier tonight for the first time in as long as i can remember (i used to do swimming lessons back in the day, got pretty far too), and I could only do 10 laps of a full-size before i was totally dead, and I work out and stay active 5-6 days a week. I'm definitely going to be hitting the pool more often from now on.
But if you want to get your leg strength up so you don't feel it as much when you hit the slopes, I wouldn't suggest getting right into dead lifts and squats unless you know proper form.
maybe try doing some body weight squats, lunges, leg press and hamstring curls (with an exercise ball preferably) for your legs
for core/back do back extensions, and any variation of crunches / leg raises you can think of
for upper body, do some bench press, rows or lat pull downs, curls and tricep extensions
for shoulders, do various low-weight dumbell raises and shoulder press. some light weight shrugs wouldn't hurt either.
As i said before, you're definitely in good shape if you're swimming every day, and your upper body and core probably don't need much work (but don't neglect them, muscle balance is key)