I've been a RE agent for 17 years. My observations in no particular order:
Extremely low barriers to entry which means new competition coming to the market every day. You can't throw a dead cat around my area without hitting a real estate agent. Double so in a down economy when people are losing their jobs.
You're expected to be available nights and weekends (at least for phone calls). Thankfully, most clients respect your time, but not all do.
If you ever want to go on vacation, you'll need someone to cover for you.
It seems like everyone wants to do a "commissionectomy" on me at some point. I'm always having to protect my interests.
Agents in high value areas don't make more money on average. There are just more agents.
Half the deals you will do all the work, but it will not close for some reason and you won't get paid. You just don't know which half.
When you do get paid, you have to pay your broker (or rent), your gas, cell phone, insurance, marketing and advertising, assistant (if you have one), etc.
Michael in ABQ is spot on. Most agents don't make anything for several years. Then they make very little. It's more like 90/10 in my market. Especially for the residential folks (I'm mostly commercial and land now). Most wash out within 5 years.
Having a very identifiable or unique last name is one of my greatest assets. Well over half the time I introduce myself to someone, they say "Oh I see your signs around."
For you, it may be worth it to have the license just to have MLS, let yourself into prospect houses, sell your own flips, etc.
If you stick it out and bust your butt, you can make really really good money. But I'm telling you it will take a min of 5 years and that would be lightning speed.