Whilst pregnant with my daughter I continually had colds (6 in all I think) I was told the only thing I could take (that was safe) was paracetemol, honey and lemon or Halls Soothers. I was told by my midwife DO NOT take things like Strepsils or Ibubrofen!!
Try and rest as much as possible with a hot water bottle, also if your decongested try sitting in the shower room with the door closed and shower on full whack to create lots of steam, which I found helpful. Try and drink as much fluid as possible - replaces all the fluid you loose due to mucus / blowing your nose etc.
Hope this is helpful and I hope your feeling better soon.
Thanks all. I think I might make an appointment at the GP - I've now got big white ulcers on my throat/tonsils so not sure if its some kind of throat infection. I don't even know whether they will prescribe anti b's ??