My shopping dilemma

I have a major problem when it comes to shopping. My problem is that pretty much anytime I go to buy something, the store is completely out. Here's a story to explain my situation:

I bought a skirt at the Old Navy outlet in Park City last Friday. I desperately need things to wear to church and it was only $10.99 so I didn't feel too bad buying it. The hard part was finding a shirt to match. I walked into all the stores at the outlet mall and had no luck. Before heading home, I stopped at Target. I found the perfect shirt. It looked great when I tried it on with my new skirt in the dressing room. The only problem was that it was a little too small. I thought it was a medium so I grabbed a large on my way out. I paid for my shirt and tights and felt very good about my purchases.

Later that night, I tried on my new outfit for Blake. The shirt however, was too big. Even though I thought it was a medium, I must have tried on a small when I was at Target. I should have bought a medium instead of a large. I knew that even after I shrunk it in the dryer, it wouldn't look good. It was only 9:00 pm, so I decided to go back to Target and exchange it for a smaller size. No luck. Even though I had seen a medium just a few hours before, they were all gone. I was disappointed but decided to see if I could make it to the American Fork Target before they closed. I made it but much to my despair, they too, were out of mediums.

Saturday morning, I called every single Target in Utah and none of them had a medium in my shirt. I was so discouraged. How could they all be out of my size? Luckily, Laci invited me to go back up to Park City that afternoon and I was fortunate enough to find a different shirt that went well with my new skirt.

This story isn't a new one for me. It seems like I deal with this quite often. Here are a few more examples:

1. I go to Walmart specifically for swimming diapers for Sadie. They are out of her size. I then drive to Target. Same thing. They are out too. I end up paying WAY too much at Rite Aid so that we could go swimming that day.
2. Walmart was completely out of instant Jell-O pudding the day that I needed it for a cake that I was making. I ended up going to two other stores before I found it.
3. Same thing happened with a skirt I bought at Target. Luckily, after calling several Targets, I found the size I needed in West Jordan. Yes, I drove over 45 minutes for a skirt.

That's enough of me complaining. I'm just wondering though, does this happen to anyone else? Or am I the only one that seems to need/want the most popular items in the store?