Am I in the wrong here?

My mum is moving back to Virginia and didn’t get a pod big enough to hold everything to move. I am staying in Wisconsin here, so she keeps asking me if I can take this or that or hold on to this or that for her. I currently live in a two bedroom apartment with my husband and it honestly feels like we’re already bursting at the seams. I agreed to hold onto a picture for my brother and will put it behind our couch to keep it safe, but mum asked if I would hold on to her bed until they could afford to send for it or come back for it. I told her that we really don’t have any room to hold onto her bed frame (I was half asleep from a nap at the time and didn’t have any problem solving mentality at the second either, but I know we don’t have room). So my mum said “fine, you’re right, I just need to learn to let go. Talk to you on your birthday. Sorry to bother you.” She said it super angrily and I just… feel bad… I’ve already taken a bunch of stuff and have tried to find new homes for some things I just don’t have room for. I will already be taking my childhood loft bed if she can’t sell it and give it away or sell it for pretty cheap (my brother was using it while they were here but wants a different set up now). Am I a bad person for saying no? >~<
Am I in the wrong here?
Post Opinion