Need some help

Hi! I just had my baby girl almost 3 weeks ago. She was born via emergency c-section at 34 weeks. She had to spend a week in the nicu but is doing great now. I'm a little worried though. I have noticed in the last few days that my milk supply has gone way down. I was getting like 3-4 oz on each side every time I pumped and now I'm only getting 1.5-2 oz on each side. Right now I am still able to keep up with her feedings but I know once they increase in volume I'm not going to have enough at the rate I'm going. I have no idea why it decreased. I have to pump and bottle feed her for the most part because she isn't strong enough to get a full feeding by nursing. (But we try a couple times a day and then she gets a bottle after) I know it's not the worst thing ever but I REALLY do not want to formula feed. I am starting to get stressed out which I know isn't helping but I can't help it. Do any of you have any advise on what I can do to increase my supply? I have a call into a few lactation specialists in my town but Would still like some other advice. Thank you!