I have a question.. I had to go off feeding my ...

I have a question.. I had to go off feeding my baby as I had to have some anitbiotics due to an edima... I was able to start feeding again when she was about 7 weeks she is now 9 weeks... the doc has given me a tables to help me bring the milk supply back in... I was just wondering will expressing help me to produce more on top of what she is getting now? I still have to top her up with formula after she has the boob... fisrt thing in the morning it is slightly different though cos she has the bood and sleeps for an hour before she wants more... I feed her at 8pm then at 2am and again at 6am.. it is the 6 am feed that she sleeps for an hour. why would this be?? this is my second child and breast feeding is kind of new to me as with my son I could only get the colostrum and 2 days of milk into him before having to stop.