Formula Copied Correctly but output was duplicate of the previous cell

Today I created a formulae in a cell and copied it down my spreadsheet and then created a lookup using the formula output. I create this spreadsheet every single day, but today the formulae copied down the entire spreadsheet resulting in
=A1&A2&A3 result A1A2A3
=B1&B2&B3 result A1A2A3
=C1&C2&C3 result A1A2A3

The formula was correct throughout the entire worksheet, but the output on every formula was the output from the formula of the first line. Was auto calc disabled. I didn't think to look b/c I was swamped, but I rely on this spreadsheet all day.