EBF Mommies am I crazy???

So my lil man just turned 7 wks yesterday and is EBF. We are currently visiting my hubby's family and he/ they decided to buy formula as a "just in case we run out". I explained to hubby we wouldn't run out since I have an endless supply and do NOT want him on formula. Well we went out on a date tonight, I left pumped milk for one feeding via bottle while I was gone. They apparently thought it wasn't enough and gave him an additional 2 oz of formula after my milk. I get that formula isn't poison or anything but I was truly heartbroken when they told me and I broke down in tears. I have worked so hard to be able to EBF and feel confident in my abilities. Am I crazy or over emotional for not wanting him to have any formula?!?!?!