My mom kinda had no reaction, except that's too much money. I found my dress in the 1st shop that we went to like 8 months ago. I thought it ws too much too, so we looked at like every shop that I could find, but I kept going back to that one dress. Nothing could compare. So after going back to be sure that after 8 months I remembered it as great as it was (and it was!), I bought it. I had her come with me the next day to sign the contract and she loves it and everything, agrees it is def the best dress for me, but still thinks I shouldn't have gotten it, since it was out of my price range.
I think your mom will feel differently when she sees you on your WEDDING DAY! She may not cry (I am pretty sure my mom won't), but as a whole, when everything is all together, how could she not be happy, just seeing how happy you are.
I wouldn't read anything into her reaction though, you are going to look beautiful! And it's only 26 days away!!!! Wow, congrats, so exciting!