I'd have to say - yes and no.
If you are feeling overwhelmed, then you are overdoing it for YOU; someone else might be able to do the same as you are doing and feel they needed MORE books.
If you are trying to assimilate loads of reading all at the same time, you may well get confused, especially with "meanings" - which are mutable - but which many sites and even a few books suggest are set in stone in the AUTHOR's view of them. NO ONE AUTHOR IS "RIGHT", I think ! (Meanings will vary from deck to deck as well, which will make it worse !)
If you are hooked on reading (I know how you feel there !) I'd suggest a journal of sorts (I am never sure how many sorts of journals people here have but...) where you can keep a couple of pages blank and ready for each card, and as you read something that strikes you - add it to that page, so that each card is all in one place, and so that you can see the variations easily. I sort of did that when I was doing the 78 card study on the Thoth - I read up on each card in several books, and noted it all down before deciding what I thought, based on all that and my own evil opinion.