Time for a Pregnancy Test?

Katie
Hey ladies!
I'd love any advice or help! I'm currently about a week late for my fairly regular period. I have a Nexplanon implant so I generally don't worry. However I've been cramping (something I don't normally do) for two weeks straight. I've also been extra nauseous, bloated, and REALLY gassy. 
Should I take a home pregnancy test or is my birth control probably doing its job. I'm starting to panic but it might just be symptoms of stress according to my friend. I also just talked to my boyfriend and he said I've been acting super weird lately and having mood swings the past few days, that could be PMS but like I said I generally don't have many PMS symptoms.
I'm super scared so any help would be great !