Pack leader

My gf thinks I don't act as the pack leader for our dog because I don't always correct him if he tugs on the leash while on walks and since I rather not be seen in public carrying a water gun, which also doubles as a weapon of last resort to correct the dog's misbehavior. The fact is that I've improved as a dominant pack leader over time and the dog is definitely more trustworthy of me. All the while, my gf still remains a pushover as evidenced when I awake with the dog snuggled up, under the covers, by our feet despite the fact that we agreed not to let him sleep on the bed. Keep in mind he's a chihuahua so you can rule out the theory that he jumped on the bed while we were asleep.