spits up or throws up

my daughter is 6 weeks now. I am feeding her how I fed her before and she had been throwing up after every feed. sometimes she even asks for more and I do feed her more, however she spits up. at times she spits up even after an hour and a half later. it usually is curdled. I don't understand why this is happening after every feed. can anyone help. Doctor suggested I give her domstal twice a day. it doesn't seem to work much. should I continue feeding her the same way or reduce her feed? she still seems hungry after feeds though. I am pretty confused. I am a first time mom.