I think it's too fomal to tell your loving feeling. In japan, instead of saying "I'm looking forward to seeing you.", we usually say "I wanna meet you soon."=早く君に会いたいな． If you love your girlfriend truely, you should be more directly! haha

I think it's fine, except it should be "I'm looking forward to see you.", but another way of saying it would be "I'm excited to see you" or "I can't wait to see you", they don't mean exactly the same but would work, in my opinion.

If you mean "looking forward" then I think it should be: 君に会うのを楽しみにしているよ。 There is no need to say "watashi ha"