Thanks Nicola and BlueIris, it was reassuring to hear your replies.

But I'm starting to get a little worried about it now. I had it fitted last Thursday, 8 days ago. I had some bleeding that day and again the next day, which was to be expected. Then on Saturday I got my period, it was due that day. My period was a little different to usual but I didn't mind that. But I'm still bleeding and today is day 7. And it's bright red blood. Usually towards the end it turns either pink or brown. But all day yesterday and again this morning I'm getting these sharp stabbing pains. And the strange thing is that they feel more like they're in my bowel than in my uterus. I don't know if this is something normal, is my body just adjusting to the coil, especially when I got a period 2 days after having it fitted.
I'm not sure what to do but the bright red blood and the stabbing pains are starting to worry me