Hey Sage, your first day actually sounds great!
I mean, I understand, not everyone “gets it” on the first day. Thumb the sweat off your nose and go at it another day. :)The cool part about these pheros is that… even though YOU might not be noticing at first, other people are reacting!
It’s just a matter of time before you notice, too. 
In time, you’ll become vastly more aware of people’s body language, and their overall subtle ways of communicating with you. You’ll get a really really good “feel” for it. It’s said that men aren’t wired to really NOTICE social effects (which is a phenomenon many jokingy refer to as MPB), but just like a muscle, these skills can be worked on til they’re ripped!
Stick these markers in the back of your mind, next time you’re around someone.
Where are their shoulders and spine facing? Toward me?
How much eye contact are they making with me? 70% 20%?
What is their movement like? Swaying? fidgeting?
Where are their hands? Do they seem to be pointing at something? Are their hands on their hips, subconsciously pointing my awareness to their crotch? Are their arms folded? Are their hands facing me in surrender?
I provided those questions just to get you started. I know you;ll come up with more that will fit your personal environment much better. When you become more observant of peoples’ behavior, do let us all know about it! I’m ALWAYS up for hearing about different peoples’ interpretations of body language! It’s how we learn from each other.
Keep at it, kiddo. If you have any ???s, feel free to give me a call.