Was this the right thing to do?

So my english teacher just got diagnosed with cancer, so we got a new teacher today. the english cl that i am in in the only one that this teacher teaches for my grade. so today in cl our new teacher asked what we had been doing the past 2 weeks while our teacher was out and i responded " we were working on creative writing". which i thought was ok seeing that we have been working on CW for the whole term. but after cl a fellow student said that the whole cl was about to kill me when i said that we had been doing creative writing. so what i want to know is was it wrong to tell the teacher about creative writng or was it wrong? also the new teacher is not going to collect the creative writing.