Can't do multiple columns or rows of cell merging (CTRL not working?)

It appears that my ctrl button is not working only when I try to merge cells for multiple columns or rows.

I have a worksheet that contains info on packages I receive at my office:

Date received

Shipper's state

Shipper's name

Package weight

Package contents

Contents' quantities

etc.

When there are multiple items in one package, say five items, I'll enter the item one by one, and then merge the general info cells into one. So it would have one received date spanning five rows of cells (merged) with the five content items listed in the next row, each in its own cell (row).

I noticed that all of a sudden, I can't merge multiple clusters of cells at once.

I select the five rows I want to merge, press ctrl and do the same for another column, repeat a few more times,

but the only cells that merge are the last ones I've selected.

I've also noticed that I'm unable to select and drag to copy a formula.

I haven't updated my excel and no one's used my computer, but over the last 20 hours I'm being inconvenienced.

I've never had the merge problem before. As for the formula problem, I have "Enable fill.." checked under advanced options.