Is it too late to switch military branches?

All branches have the same benefits. Same pay based on rank, same medical, same education, and more. The only difference is that since pay is based on rank you'll most likely get more of it in the Army since the Army promotes faster than the Navy on average. The statement "so I heard" is a huge downfall. If you want to go to the Navy that is your choice. You'll just have to speak to a Navy recruiter and they can get your records for your ASVAB and physical transferred to them. But if you decide to go that route do your Army recruiter a favor and tell him or her. Don't just blow them off, hide, and screen your calls. If they know you're not interested anymore they'll leave you alone and they won't waste their time trying to get a hold of you when they can be trying to find somebody else.