Memory problems. Precautions can i take?

Over the years, my memory power has declined gradually. Memory power I had during my teenage is not same as I have now. Till recently, I felt it is normal. But, since a week I have a worrisome feeling. Lately sometimes I am not able to remember things which I have seen or heard very recently. Sometimes I find it difficult to remember what I had seen or heard recently (certain things, not everything). Also I find difficult to recognise or remember certain people like actors or players when I see. But, earlier I could easily recognise the moment I saw them. In general I feel my memory power has declined and few things I cannot remember easily. Earlier, I could easily remember recent things, lately I find difficulty remembering certain recent things. I'm not under any medication, drugs or alcohol. Sometimes I feel scary that I am experiencing such issues at this age. What should I do and what could it and what precautions can I take?? I am hoping it's not a serious concern. Please advice.