ADHD or Memory Loss or Other Neurological Issue?

Patient: I am having problems remembering things that just happened or conversations. For example the other night my fiance had just gotten home I was doing the dishes he said something to me I responded and he eventually came over and gave me a kiss, I finished the dishes sat on the couch all upset that he didn’t give me a kiss and I told him that and he asked if I was joking and I asked what he meant and he said we just kissed like 10 minutes ago. I have also had problems during conversations for example I’ll be telling someone a story and in the middle of it I will literally forget what I was talking about and just kind of say and well yea. I am very concerned, this is more of a recent problem within the last 2 years but now im experiencing mood swings from content to depressed often and I am not on any medication. Does this sound like ADD or some kind of memory loss issue? I should also add my sister just had brain surgery for a benign tumor which caused her to have seizures.