Speaking as someone who has used a wheel chair for medical reasons during con (when I was full term preggers mostly at the end of the day) any costume that is cumbersome ie hard for people to get around etc, is going to get a few dirty looks or comments from people who have decided you have inconvinced them,(but they are going to be the type who need to have something to complain about, even if its a 9 month pregger lady in a wheel chair) but that happens, and it shouldn't keep you from doing the cosplay you want.
That said, I don't know how well you will be able to move or if your vision will be impaired by the costume, if it does then I recommend having a handler (some one with you to make sure you don't run into people or block peoples way and such) someone with you. for example my brother has a father cat and he can not see at all in it so I would walk with him.
from what you have described it shouldn't bee too bad, and I have seen much worse from people with out handlers who really should have. Also if going to a pannel I would recommend leaving it in the room as pannel rooms can be a bit small and filled with people, if you took it off and left it in the back while sitting it could acidently be damaged. For events in the main events area, there is plenty of room to stash it next to the walls.
But yeah as long as you are aware of your surroundings and other attendees and plan accourdingly I think you should be find. As for comments people that sadly can just happen and shouldn't stop your fun