Aww, brave little doggie, I loved my first walk with Bella, she was completely bomb-proof!
The crossing in front of you and tripping you up thing, you could start teaching her a bit of heelwork - i.e. get her to always walk on the same side all the time, on your left or on your right (doesn't matter which but make sure you're consistant with it). Give her treats as you're going along to encourage her into the correct position - it's early days so have patience with her but it's always good to start early IMO.