Ineedhelp, have you scheduled an appointment with a gyno yet? I think you'll worry less when you know that everything is normal.

It sounds like he's been bumping your cervix-- this may or may not hurt during sex (it apparently depends on the person), but it can cause bleeding and cramping for awhile afterwards.

Try going on top and making his penis stay allot further out of the vagina. if a penis goes to far in it will bump the cervix that can cause extreme pain. some couples tie a bow around the penis so that they know how far to go.