Pregnancy after miscarriage

Anyone have thoughts on pregnancy after miscarriage? I didn't have a cycle in between the miscarriage and having a positive pregnancy test. I miscarried 12/27/15 and just got a positive a week ago today. I took a clearblue digital with weeks estimator and of course came back positive with 3+. On 2/9/16, I had betas drawn and it came back negative. I'm racking my brain trying to figure out my due date BUT I will try my best to patiently wait until my first ultrasound!