Am I doing Kegels correctly?

This question is for women who have a done Kegels regularly. Here is what I have been doing: I try to keep my abdomen, my thighs and my rear end relaxed. I contract or “lift” the muscles inside my vagina and what feels like my cervix. I hold it for about 10 seconds and then release. I wait 20 seconds before repeating. The reason I think I am doing it wrong is that when I contract my vaginal muscles upward my anus tightens as well. I literally feel my anus contracting. Have any other women experienced this? It seems like it would be impossible to contract my vagina/cervix and not feel some tightening in my anus. Is this somehow a sign that I am doing it wrong? I am hoping to get pregnant so I am doing these now in order to strengthen that area (hopefully) for a birth.