Definitely go, as Starlight said, its a slippery slope and I speak from far too much experience at that. Countless times in the past Ive weighed myself, found Ive gained or sts and decided not to go.....and never went back hence the gains in weight.
I made a decision this time to always go regardless, in the past Ive not gone back because Ive sts or lost 'only' half a pound, have given myself loads of kicks up the proverbial as its not always going to be easy and yes there will be times when I'll cock up/become disheartened etc but if i keep going the chance of me getting to goal are way higher.
Its def worth going, you'll get the support you need and the motivation also, you'll feel so much better honestly!