Learner's permit story: what percentage was I in the wrong?

My dad and I decide to take a trip to Wawa, deli convenience store in our area. I ask him if we can go to one a bit out our way for the driving experience and he get befuddled since he likes things in a predicable pattern and gets frustrated easily. It's after dark and my phone lays out the quickest route. The trip there is almost uneventful except I make a wrong turn on a residential street which I U turn to get back on the way. There were no close calls there, just parked to the side and waited to make the turn around. But I noticed he was fidgeting the whole time. I pull into the lot at the strip mall where the store and it goes without incident. We pull out and I head to the road but as I creep out, my dad calls for me to stop since we noticed there was a barrier between the lanes so I couldn't make the left I wanted to. There were no cars from the left I needed to worry about and I didn't go more than a few feet before I backed up. There was a "No Exit" sign I missed but it was tilted away from my approaching angle and the light was low. There were arrows pointing inward but again, the light was low. There was only a barrier between the lanes in front of the strip mall and it was weird I couldn't even make a right at either entrance. I admit fault at not seeing those things but my dad almost didn't see them either.

So I'm wondering how I get out of the lot, we followed a path to around around to a slim path on the side of the lot that lead to a smaller road you'd need to make a left on to get back on the road we took to get in. There was no barrier between the lanes there. As I pass through, an large pick up truck passes me on my left. There was no close call there but the maneuvering needed to get around it was inconvenient. I was worried I was going the wrong way for a second but there was a stop sign beyond that so I knew it was indeed a two lane path in the lot. Branches on the right grazed the car. They left no mark obviously. I make the left on the road, then a right to go back the way we came.

My dad started yelling but not so much about my driving but just getting pissed off we didn't go to the store we were familiar with. He was fidgeting the whole ride and I went off about how I needed to do more driving than roads I'm not familiar with for experience. He kept repeating his frustration at not going where he wanted. I called him baby and said I didn't understand why he was making such a big deal about a trip less than one mile further than the store we know.

When we get home, he apologized and admits he cannot tolerate stress relating to his mental disorders like bi-polar. He frustrates me sometimes, his emotions are like a two year old's sometimes. But I reply by apologizing I didn't see the (crooked) sign or the barrier. I say the next time we go somewhere I'm less familiar with, it will be during the day. But he also needs glasses he doesn't wear and I've asked him to wear them while I drive to help me out. He still saw it first which I admit but the whole thing is frustrating. I looked at the lot from google maps' satellite feed and the lot indeed only had a few strange two lane narrow paths to get out. Why can't you exit out those two big entrances? Even to make a right? He looked at it and agreed it was strange.