Loss of interest in sex and relationships

So within the past week I have been feeling very depressed, and it all started when my abusive ex texted me. I had a small chat with him, but it didn’t go beyond that. I wonder if it brought up past trauma, and sent me into a depressive episode. I have lost interest in the idea of sex, and the idea of getting into a relationship again. This is all very weird for me, because I’ve always been very sexual, and I love being in relationships and talking to new people. But, also at the same time I started taking some new medication for my ADD (Ritalin) and a medication to help my acne. I don’t know if I should stop taking my medication and see if that helps, or just keep taking it until I see my doctor on January 3rd.