Hello Mrs Fish and welcome
I was in exactly the same position as you - a missed mc and then pg soon after. Quite a head-messer, as with a missed mc there is no indication that things are not going well - therefore whatever is going on seems ominous. What tends to be recommended on the thread - push your GP or contact local Early Pregnancy Unit for an early scan (7-9 weeks... although I got scanned twice, because the first scan showed the baby at the same stage as the baby that died, they scanned again 2 weeks later to make sure the new baby got over the difficult stage) and try to fill your days with relaxing stuff, or things that keep you mind occupied, with lots of treats scheduled to look forward to. It does get better.
I always recommend the Lesley Regan book Your Pregnancy Week by Week. She's a specialist in mc and covers this topic, and subsequent pregnancy fears, very well in the book. Plus there is lots of information about symptoms like cramp etc which had me confused first time round.
On BBC KnickerWatch idea. Last time we were at London Zoo, we saw Bill Oddie doing some filming. It was a bit disappointing, as you kind of expected him to be chatting to passers by, or at least humming 'the funky gibbon' and grinning to himself but no, he was just hanging around looking a bit grumpy. Maybe not the presenter with vim and verve who would be right for KnickerWatch