Leak through concrete after putting frames up

Hey guys, real stressed out here.
So I'm trying to create another living space in the garage, and I've put the frames up recently. With the torrential rain today in Melbourne, I went outside to have a look for leaks that could be coming through the roof, only to find puddles of water. Figured the source of this was from the dynabolts that I've drilled coming from the bottom (correct me if I'm wrong), as I've never had this problem until the frames went up. The concrete must have been fairly shallow, and I possibly drilled all the way through?








I'm thinking I have to take the frames out and repairs those holes as #1 priority... but after that i'm not sure how I would fix the frame into the concrete without this repeating. Will I need to waterproof the whole floor? Epoxy? I have no bloody clue.
Can anyone help with a solution? Thanks so much for reading and hoping for some good input!

no, must have got in there some other way, either roof leak, or maybe where garage door was.

If that water was under the slab then you are, and were going to have huge moisture problems regardless.
I would think it's got in somewhere else otherwise you may have to rethink your plans of turning it into a habitable room.

Are you doing this with a building permit? Conversion of a non habitable room into a habitable room requires building permit.