Tablecloth troubles

I've been trying to sew a tablecloth all day.
I hear you think: "That shouldn't bee too hard since a tablecloth only needs 4 somewhat straight seems". It's not the straighness that has kept me fidgeting all day. The thread/machine (or both) is (are) plotting against me. And to make it (them) cooperate takes quite some time.

Grrr!!

But when it's done it will be a lovely tablecloth (I keep telling myself...)