I am sorry that you are having to deal with that in the middle of the night
Starting at about 11 months my guy was getting fussy because the milk wouldn't let down fast enough as he was used to his afternoon baottle being so quick. It is very frustrating!! I just kept putting him back on and telling him over and over "Don't worry, it's coming". He seems ok now with it though.
I think you just need to try and relax! Ya right eh?!! I remember when I used to pump before Carter would get up in the mornings when he was an infant. If he would strat to cry while I was pumping or before I was even able to start I would have a breakdown ... totally stress out because he was crying and then it would take forever to pump. I started to dread every morning until he got a little older and I realized that he wasn't starving and everything WOULD be ok if I took a few minutes to pump milk that he needed for the rest of the day. I made myself take deep breaths, shut the monitor off (unless he was frantically screaming the house down of course) and relax!
It also helped alot if DH was around to entertain him! Could your DH get your DD out of bed for a feed while you are getting yourself prepared so that by the time she gets to you, you are already relaxed and ready to go? Don't feel dumb for having to stimulate let down on your own.
Women do many many things to ensure their baby is getting breats milk
If doing that is what helps you right now then by all means go ahead and do it! In the meantime just try and work on relaxing during feeds. Look .. you've already raised a beautiful healthy strong 7 month old!!! You are definitely doing something right!!!!
HTH