What Are The Signs Of Perimenopause?

I ve always been regular with my menstral cycles, I m 41 feel great active and all of a sudden no period since thanksgiving 2014. I m married sexually active my symptoms are similar to getting ready to start but I don t. I took two home pregnancy tests two weeks ago both were negative. Is this pre menopause? I have no hot flashes, I m not dry or experiencing pain during sex... Can you offer insight?