HELP! HCG Levels

Danielle

So I'm mildly freaking out. I went to the doctor last Tuesday and my HCG levels were 14,400. I went again on Thursday and they were only 18,800. Arent they supposed to double in a 48 hour period? I still have all my symptoms and I havent had any bleeding. I'm wondering if I'm just being paranoid since it's my first time being pregnant or if this could be a indication that something's wrong. Experienced moms, any thoughts?