6 DPO is it possible to feel symptons that soon?

Katie • Katie
Hi there!
The past 4 days I've felt slightly nautious (no actually throw up) and have been light headed at times.  What I'm feeling isn't a constant feeling more like comes and goes. My husband and I have been TTC for almost 4 years with no luck.  Of course I don't want to get my hopes up, but I'd like any opinions, help or support.  Any tests you recommend and how soon I can take it?  Thank you, ladies!