Flowering lady not swelling?

Looks okay for week 3 to me depeding on your nutrients they should double in size or even more in the next 6 weeks. Though if you feel she is not growing as she should you could always try and increase her feed slightly that would most probably help her out and the yellow leaves are common when in early flower at the top would mean the ph is probably fluctuating too much which could slow down flowering. It could also be pheno related if she is from a different seed she just might be a tad slower than the others with nothing to do with you. If you grow a seed no matter the strain its a completely unique plant. Usuallly it will not grow identical to the others as the lineage is different for each strain. fading yellow leaves that start at the bottom and work thier way up is usually a sign of a lack of nitrogen in the feed. Nitrogen is a mobile nutrient she will use N right up until flush :) looking good anyway bro look into some organic extracts that contain amino acids to give your plant an extra boost in energy. If you want to prevent this in the future and want a brand of nutrients with the base elements NPK along with all the organic compounds needed for optimal plant health then hit me a pm I have a special discount code I can offer you from a brand new line of nutrients based in the netherlands :)