Anyone on here gotten pregnant with an iud still in place?

Emily • Pregnant with #3! Due May 6th 2015
I've tracked my periods for a long time but never anything else since hubby and I aren't trying yet but for some reason this month I just felt like I was preggo... And maybe since I thought that I'm just more aware of what's happening with my body but I have an avg cycle of 28 days and one period tracker I have estimated O on 3/14. On 3/17-3/18 I had really bad cramping and a lot of CM and even some brownish pink tinged CM. I assume that was when I actually O. Now 3/25 I'm having cramping. Is this all normal cycle stuff or should I take a HPT
​I think I'm going to schedule to have my iud taken out and we may actually try next month if I'm not this month.