This patient support community is for discussions relating to relationships, abstinence, arousal problems, birth control, cohabitation, commitment, communication, couples counseling, desire, sexual technique, and sexually transmitted diseases (STDs).
As more general advice, I don't know how long you have been trying, but I wouldn't get too hung up on checking your fertility all the time and obsessing about whether you are or are not pregnant this morning. Just enjoy having sex with your husband and the results will come. For many couples they don't get pregnant right away however hard they try, give it time it will happen. You clearly are both fertile if you have two children already, and at your age I really don't think your fertility should be reducing at all.