guys I'm freaking out

My son is 4 months old today and for the past two days I have been completely nauseous and had an extreme headache that nothing helps make it go away...also when I was pregnant I couldn't have sex without crying (dr told me it was just the hormones sex releases) well I had sex 2 nights ago and balled my eyes out. I took 2 88 cent tests last night from Walmart just to see what they'd say, both said negative. Am I just being paranoid?