No apparent LH surge, should I be worried?

[bulldoggrl]

Hi, I am new to this site, and I am looking for some information. My husband and I are trying to have our first child. I have never been pregnant. I'm 35. I have been using an ovulation kit daily for over a month and I am not picking up a positive LH surge. My periods are normal, and I know I am a little on the older side, but I have known several women my age who have had babies. Does anyone have any thoughts? I haven't seen a doctor for this as we have been trying to let nature take it's course. I guess I am just feeling a bit lost. Thanks!