I have just began my first year as a math graduate student at a US school. I am having an issue in the fact that
During my undergraduate years, I would only take 2-3 classes a semester, and usually only one or two of them were a math class. This got me used to a particular style of learning; I always had as much time as I wanted to spend on any particular topic; I would read about the topic from different books, read about the history of the topic, etc. I feel like I learned very slowly, but what I did learn, I learned well.
Now I am in grad school, and the atmosphere is completely different. I have 3 math classes which move very fast, and assign a lot of homework. I feel like I do not really have time to learn the material well; I learn the material just barely enough to to do the homework and pass the exams, and then I have to immediately push on to the next topic. I solve the problems and try to understand the theorems/proofs, but then one week later I often retain very little. I always feel like I need 2-3 more passes over the material to learn it well, I never get a chance to do it.
I feel like some of those undergrads who just learn the material to pass the class, not really to use it. But this is terrible to do as a grad student, since math is supposed to be my specialty.
My question is, is this common? I am trying to figure out if this is normal, or if I handicapped myself in undergrad by taking it too easy. It seems to me like there are some students who retain information much better; they study much less than me, and seem to recall information from weeks before, and I can't do that.