Accidents Happen

So today has been a frustrating day in the world of potty training! What makes it the most frustrating is knowing Colby can go weeks without having any accidents then there is a day like today where he has 9 or 10! I lost my temper and patience with him today which now I feel so bad about though!
It all began with today at the playdate I didn't take him potty over there which I should have. I guess I honestly didn't think about it since no one else went to the potty and its always a little wierd going at someone else's house so I knew he would have wet his pullup there so we got home he went to the potty though and I changed him. I let him know its ok he wet it while we were gone b/c mommy didn't take him to the potty. I put him back in underwear though hoping it would make him realize we were home now and we weren't going to pee on ourselves! Well he was off playing and next thing I know he had pooped in his underwear! he has never done this before! He usually waits to do that until he has a pullup on or diaper at night. Unfortunately he hasn't made a lot of progress with that...he has pooped on the potty like 5 times but it was almost a month ago now and he just won't do it but I haven't pushed it either I figured he would do that when he was ready. So ok I cleaned up one mess so the rest of the day I felt lazy and just put him in pullups I really wasn't ready for anymore messes!
He always pees during his naptime but again I expect that because he is in his room for 3 hours. He hasn't grasped telling me when he has to potty yet I still have to remind him or I catch him with body language or sometimes he leads me to the bathroom. He peed in his pullup about 3 or more times after his nap which he never does! And we were home with me taking him potty every hour! I don't know what his deal was! I am not sure if he got all off routine with the playdate this morning and it being acceptable to pee in his pullup or what?!? I had to get firm with him tonight because I really had no other way to get through to him that its not ok to pee on yourself! I hope tomorrow is better and I know I should be patient since he did just turn 2 and most boys don't get it until close to 3. Its just going to be a hard year as far as making sure he goes to the potty all the time and worrying about accidents I think diapers were easier! And its so tempting to go back to diapers but I really don't want to do that! I just feel like its a never ending process!