u/Ecstatic-Pin-7970

So I just beat GMS and apparently that's it? I feel so unsatisfied and incomplete because it feels like there is so much more. I've only got 7 masks, I haven't explored 7 of the places, I only got 3 crests, and I thought act 3 would unlock after GMS. I feel like the game was extremely short, and I bet it in 26 hours, which is half the time it took me to beat hollow knight, and I'm sorry only 18/51 tools??? If there is an act 3, can y'all give me hints to find it with minimum spoilers?