How to deal with accidents!

Well i'm sorta new to the whole vegan thing we are going on 3 weeks haha ok so really new though i've been an off and on vegetarian for 12 years.  If you know me I hate to make mistakes it's just not a pretty side that comes out of me just not pretty, anyways while we were shopping the other day we bought what was packaged and thought to be vegan cheese :( sadly once we got it home and started eating a little of it we realized it in fact had casein :( well it's been sitting in the fridge for about a week and out of the fog of my mind today decided to make a veggie burger and just saw cheese and grabbed it I immediately felt bad once i realized what i was eating and threw away my burger ! Looking back that may have been a little rash haha because now i'm just hungry but  I saw a thing on facebook today that said to look at "perfection" as a vegan as impossible because its easy to make a mistake. Say you only make a mistake 1% of the time then look at it this way at least you are doing something right 99% of the time. That kind of calmed me down a little. The reason behind my foggy head was I took my babies Tumbles and Chewie to get spayed and neutered :( I'm not keen on doctors of any sort but we just had a litter of four sweet puppies which we kept and know that we need to do our part in helping control (i hate this word) the pet population and they both had to get rabies shots :( I wouldn't do it if it wasn't required by law or they would take them away from me. We don't vaccinate our animals and when we have children we will not vaccinate them either. Anyways that's why my heads been in a fog ive been chasing around 2 dogs who don't care they've had surgery :( Bonus my hubby made me more funnel cake cookies which im sure i just ate too much off haha!