Adventures in Potty Training

So as i mentioned earlier B did great at going potty yesterday, so today we decided to try big boy underwear instead of pullups...which was great until we decided to go out and run some errands. I gave b the choice of keeping his underwear on, or putting on a pullup ( I WAS PULLING FOR THE PULLUP) he said big boy, i was very proud of him, but VERY stressed out about it...here is how it went leaving for Bishops and the gas station, the 2 places we needed to go. i made him go potty, he went, we got in the car I said remember if you have to go potty tell mama.. he says I have to go potty (still in the driveway) ok..run in go potty, get back in the car get maybe 3 houses away..MAMA I Have to go potty..turn around drive back to the house..(FYI the gas light was ON). Go in go potty get in the car and drive to Mobil and PRAY that he doesn't say he has to go there, lucky for me he didn't..Get to Bishops, are in line PAYING and he tells the cashier I HAVE TO GO POTTY.. I look at her DESPERATLY and ask if they have a potty, she says yes outside around the building...We go in, the bathroom is not as clean as my potty at home (I am super fanatical about bathrooms)..line the seat, b goes and we got in the car and drove home...perhaps we will never leave the house again...
I know that it's all me, that HE is ready, and that I am the one w/ the bathroom issues...Also B's potty training has all been what I like to call "SELF DIRECTED" i came up w/ this on my own and it has been what works best for us..I am so proud of him...sorry about the long potty blog...