He Keeps Me On My Toes

Aspen is a loving, sweet boy, but is also very challenging, high maintenance and manipulating.
He has been very challenging for me in the last couple weeks. I have a few stories of what he has been doing.....

Every time we go to our favorite coffee shop, Coffee's On, Aspen gets a chocolate covered gummy bear instead of us getting a chocolate covered coffee bean. It's one of those things that you let happen once and they never forget. I work hard to make sure he says "thank you", but this particular day made me realize that he needs A LOT more work in this area!
So we go in and he immediately starts jumping up and down chanting "I want a gummy bear! I want a gummy bear!" over and over. Ahhh! My blood pressure is already starting to rise...
I am holding Journey, trying to order my drink and am also trying to get Aspen to stop. This is embarrassing. The girl gives him a gummy bear and he now starts asking for two. I try to tell him "no", but they offer him two. But then he changes his mind and wants some regular ones. I'm trying to tell them no, he doesn't need that, chocolate ones are just fine, but in the background he is jumping up and down about the regular ones and they agree. Now they produce a cup of regular gummy bears. Aspen says "thank you" as he takes the cup, but then looks in it and notices that there are no green ones (favorite color). He starts whining to me about having no green ones. At this point I am just trying to get him to stop talking. I am really embarrassed by his behavior, but it only gets worse. He is getting really worked up about there being no green ones and the girl behind the counter now knows that he wants a green one. I am trying to grab his hand so we can get out of there, but he dodges me and in the process spills the whole cup of gummy bears. Now he is freaking out, screaming and crying. There is no reasoning with him at this point. AHHH!!!! Why me? Of course the girl feels bad and gives him another cup. I get out of there as fast as I can (apologizing as I go) and as soon as we get to the car, I take the cup. He has lost his privilege of gummy bears and I am steaming.
Yes, I look like a horrible mom and it's embarrassing, but like my mom says, you see the things you need to work on at home when you are out in public. How true!

One more story. Aspen has been giving me problems with napping. Right before we go down, he always goes to the bathroom. Well, he has been giving me the "I have to go to the bathroom" routine every 20 minutes, thus he doesn't take his nap that he really needs. So a couple days ago we went through the whole routine. The second time he got up I told him that if he got up again, he would get a spanking. About 20 minutes later he is calling me yet again....
I go up and with a little smirk on his face he announces that he has just peed his pants! "No you didn't, you better not of" I say. "Yes, I did" he says matter of factly. And I just knew right then that he did it on purpose. On purpose! He wants to control and manipulate the situation so much that he peed his pants on purpose. What do I do now? I am so glad I have Mark to get more insight on this. Aspen tries to control every situation he is in and can make everything into a power struggle. I have my hands full.