Day 19, plateau?

I've been planning to go for 30 days. Wondering if it's normal to plateau on the weight loss at this stage. I think my weight's stayed the same for a few days after losing steadily in the beginning. I'm still really weak and had an extra-extra tired day today. That 21-day mark looks good to me but I'd regret not sticking it out to the 30-day goal I set my mind to at the outset. I have made it this far, and I don't want to do this again anytime soon. I had a weight goal in mind, and I'm really pretty nervous about gaining weight back with refeeding, so I want to make sure I get it down as far as I can. But I suppose with ideal refeeding I won't gain it back other than a few pounds of water rebalancing weight?