Hey, well done, 5lbs is brilliant on your first week. Remember not to expect as much of a loss on other weeks though, just don't let it get you down. But you are doing brilliantly already. I started at a weight of 357lbs and am only just under you now so I know how you feel about wanting to drop the weight etc. It is also a good idea to lose the weight before trying for a baby. I have 5 children. I was about 13st when I conceived with my first but due to a "feeder" husband, I went up to 25+st. I had all other 4 babies being 20+st so it is possible to conceive but I struggled so much with the weight and then the extra baby weight, it gave me SPD and sciatica and I was on crutches. I wish I had lost weight before I had my others and will definately lose weight before we have our next one! Yes we are planning more lol.
But good luck with the losing weight and the trying for a baby.
xx