Having some issues with Paraguard?

I had my Paraguard IUD inserted about 4 weeks ago and I've been having some issues. I bled for alittle over 2 weeks afterwards and it was heavy bleeding, not spotting. I'm also having alot of very painful cramping. I also have a very difficult time with sex. My husband says he doesn't feel like it's hitting it but to me it feels like he's just jamming into it. It's making sex unbearable. Anyone else have any issues like this? Should I talk to my doctor? My doctor actually had a very hard time getting it in and it was very painful but a few years ago when I had Mirena I had little pain when it was put in. I don't know why.