Weaning off the breast side effects?

[callypygous]

Hi ladies, I had to stop breastfeeding my LO about a week ago. I had gradually been replacing feeds with formula and by the time I stopped entirely she was only consistently having a night feed, and even then I wasn't convinced she was getting much.
I haven't had any pains or engorgement, but I have been experiencing pregnancy symptoms - nausea, light headed, metallic taste in mouth, crazy water retention and gassy!
Despite not being as careful as we should have been this month, these symptoms started v soon after I stopped breastfeeding and too soon after my o date for me to think it's likely I'm pregnant.
However I can't find much online about this. Has anyone else had weird side effects when weaning?
On another note. I miss it so much! Hoping I can breastfeed for longer next time round.