TIFU by talking on a sensitive thing like financial management to my girlfriend

I was casually talking over a call to my girlfriend whose parents are basically taking EMI to gift their relatives. I was appaled by the sense of her inability to have a say on that matter though she's the one taking care of their homeloan and other expenses. Actually she thinks her parents know better so whatever I tell against it goes against me. This month's EMI is basically given to help someone and they are short of that amount as well which basically highers their need to around 2 lakhs in need for their plans which they are trying to get into debt by pledging jewels or buying items on EMI. For my limited knowledge I thought it was very risky and was worried about our future financial beleifs. So I wanted to take up the topic of how she'll support her parents after marriage like taking care of home loan or helping them out with expenses to which I was trying to convey in a way that she should have opinion on how they spend - basically not on new loans or EMIs which will add burden to her too in future. But it took a turn where she said it was all drama when I was previously romantic and talking good things to each other, how much we admire her. I lost my cool and was disappointed in myself to have taken up this in our conversation, which might end up bad in future. Meanwhile, I just buy one new dress per year to save for my marriage to take the burden our of my parents and trying to control my house expenses. Though I should not have opinions on her decisions I feel she has no idea how I hold a lot of spending to save our future's peace while she has the idea of taking loans for everything. I said I won't do that necessarily as I always lessen my expenses and expectations only upto my ability, to which she sees me as a coward who who is afraid to take a loan. Now I beleive I should not ask my parents any money for marriage and should take a loan for myself only then she might believe my financial conditions too.

TL;DR: I fucked up our relationship perception by talking sensitive things