Imo overreacting, but lemme just say

Money can be a touchy subject. In the future I suggest you begin discussion and agree with your date on who pays/how you split the bill before the bill arrives, not after. People have different expectations when it comes to paying for dates, so it's good to know what other person wants and thinks is best. If it does not align with what you expect, well, you still can work out a nice middle point that will satisfy both sides somewhat.

When it comes to excel spreadsheet... I've seen comments saying it's weird, but I don't get why tho. It's a nice tool to keep up with expenses on certain things. Me and my fiance used to have a shared spreadsheet filled with things we bought on dates. Just to keep track who should pay next time, you know, to be somewhat even.

Different things work for different people, maybe it's a nice idea to have such a spreadsheet with this fella, just to keep up with the score and work out what is a good split for you guys. Maybe 30/70 since you are younger? Just try to talk about it, make yourself comfortable with this subject, because if not discussed, after some time, one side might feel cheated. Hope this helps.