period in 8 days and already throwing up?! wth?

Sh

okay so I just had a baby almost 4 months ago. I still have 8 days till my period start day (I have no idea what my DPO is). All day today I have been sick to my stomach and I have thrown up multiple times. Pregnancy tests are negative, hell, i still have 8 days till its supposed to start. Is it possible to get any kind of symptoms before you even get a positive preggo test? Not possible right?