Puppy suddenly acting scared of me when I get home from work

Question
Ok, to give you some background:

I have a 9 month old male miniature australian shepherd pup (named Boomer).  I've had him since he was 6 weeks old.  We potty trained him with the crate method and he learned very quickly.  We don't use the crate any more because he is completely trained.  I live with my boyfriend.  We both raised him (I have worked with him the most though).  I take him to dog parks, on daily walks, out to play frisbee, taught him multiple tricks.  He's a super smart and obedient dog.  When he was quite a bit younger, we had some issues with him trying to dominate us with biting and mounting.  We would lay him down and growl as if to establish who was dominant (we were very gentle about it and made eye contact).  My dog and I are super close.  He is a bit shy around strangers (he loves most ppl but will be shy if they are in our house) and always runs to me when someone comes over (which i've heard aussies can be like that).  I never hit/harm him.  If he is ever bad and I catch him in the act I just say "kennel" and he goes to it.  That's basically our form of punishment since we never use the kennel for him to sleep in anymore (i know ive read to not use it as punishment).  Boomer loves me and is always excited to see me when i get home.  However... here is the issue:

Last week, i came home from work and as soon as I came in I did my normal greeting "there's my puppy!" and he normally comes running to me excited, rear end wiggling.  That day, however, he kinda sulked and stayed right next to my boyfriend's leg and didn't come to me.  He acted afraid.  I called him again and he slinked over to me and urinated a little bit by me!!!  I have no idea why!  I did start a job bartending about 1 1/2 months ago but he was fine with this until just recently.  I was completely at loss as to why he's doing this.  

So the next night i get home he did it again!  And then again tonight.  I asked my boyfriend what on earth he did to him.  He ofcourse (is a very gentle/kind/loves kids and dogs kinda guy), said "nothing at all, this is so weird".  All I can think of is maybe i smell funny to him or my all black uniform is intimidating him (even though ive been working there for 6 weeks....  

After im there for a few minutes and get out of my uniform, he goes back to the normal puppy he is.  Lately i've been trying to give him treats when I walk in from work.  He lightens up with treats.  

Im just confused as to why he may be acting like this.  It's just me and my boyfriend living here.  I have been working longer hours lately.  Im afraid he's forgetting who I am!


Answer
He's definitely not forgetting who you are!  At nine months (approximate) the domestic dog's brain is undergoing development; it's quite easy for a dog in this stage of life to acquire fear reactions to otherwise ordinary and accustomed things (including having furniture moved in unexpected places).  It's possible your manner of dress has affected the dog; it's not uncommon for dogs to react with fear, avoidance and even aggression, toward unexpected articles of clothing (hats being a large problem, sunglasses, strange outfits, etc.)  Also, the smell of alcohol (although you can't smell it, that smell permeates every drinking establishment) may be contributing; the dog's sense of smell is enormously greater than our own.  The combination of dark clothing (if you don't usually dress this way) or costume and the smell on your clothing may have precipitated this fear reaction.

Don't be so anxious to have the dog greet you.  It's possible this will disappear as quickly as it appeared.  Don't offer him treats, because you're not absolutely certain what you're rewarding.  If he's still fearful but really wants the treat, his fear is being rewarded.  You can, of course, keep something in the car (like an old bathrobe he's familiar with) and put it on over your uniform before coming through the door.  You might try this as an EXPERIMENT over the next few days.  Put on the old robe and, upon entering, instead of making direct eye contact and speaking directly TO the dog (which is dominant and if he's fearful may be worsening things), greet the BF instead, ask HIM to get up and give you a hug, and observe the dog.  At first, he may be hesitant (because his present behavior is "set" for now and he will have to unlearn it), but after three repetitions of this (on three separate days) he should begin to return to greeting you.  This may persist even when you no longer use the robe; if it doesn't, you will need to ignore this dog upon your entry and wait until you have removed your uniform.  This will give him time to problem solve through this event, especially if the BF persists in greeting you happily.  If this experiment does NOT WORK, if the dog persists in showing fear upon your arrival, then it has nothing to do with your uniform at all.  REPOST in that event with all details regarding what happened during your experiment.