What were your first signs of pregnancy?

Before you missed periods and had positive pregnancy tests, what didyou first notice?

Recently my period was slightly later than usual and it was extremely light. There was no need for anything except a panty liner. Also it was slightly more brownish in colour. Does this sound like an implantation bleed?

I've also had a few other various symtoms that may or may not be pregnancy related.

Any thoughts and personal experiences would be very helpful :)