Where do I sit? Being at a new office building, waiting room

Circumstances are such that, at this moment, I am in a brand new office building, waiting room. It is high anxiety.
I registered with the receptionist who wore a puzzled look on her face that didn't make me feel any more comfortable.
Then I proceeded to "stakeout" the place. I paced, walked the perimeter reading signage, bulletins, noting where the exits were and the direction to my vehicle.
I abhor getting lost or feeling trapped in buildings. I am feeling panic and I may bolt to the front door for fresh air.
It took three or four times, walking around the waiting room, to figure out where to sit. I ended up near the front entrance with a direct line of sight to the office door. This way no one can sneak up on me. I can monitor who comes in or out. I feel safer seeing my vehicle and the door to outside.
  I feel like I'm on point, on surveillance, okay...hypervigilant. I'm quite nervous as there is so much uncertainty in a new building.
I've brought calming, grounding tools: my ever present bottle of water to hold, my phone for writing this and picture taking if I get more nervous, my meds which I shan't take as I'm tired and have a distance to drive back.
Yikes, such perilous uncertainty. People coming and going. All the smells are completely different, as well as the sights.
I have this habit of checking the shrubbery to see if it is real or fake. I feel better with real. There is a forest of plastic trees in here....fake, fake..yikes.
Thankfully the television in this waiting room is off. I can't tolerate any more sensory overload. I'm already quite overloaded and could start flapping my hands at any minute.
There are three offices serving this waiting area. Sometimes receptionists talk, chatter, answer phones. Glass windows slid open and grind shut.
The front door is fairly loud with frequent comings and goings. The floor squeaks heavy where the tile is and shifts to muffled shuffles on the carpeted area.
There is a clock. Unusual. Most waiting rooms no longer employ clocks...wouldn't want people to know how long they must wait.
Noises come from different directions, stairs, hallways, and about a half dozen doors.
If you ever get nervous in a new place, write if you can, take pictures of your surroundings if allowed, stay in sight of one or more exits.
We are Aspie....this is our norm.