Why are so many Indian mutual funds giving negative returns over last one month?

If we look at the performance of several Indian mutual funds over last one month, we see that many of them are giving negative returns. Some examples are: HDFC TOP200, UTI dividend yield, Birla sunlife dividend yield plus etc. Can anybody please explein why this is happening? Should an investor be alarmed if he had invested in these funds? What should one do in such a situation?
I am a new investor and feeling depressed to see that market values of all my investments are negative. However I heard someone saying that one should buy more units of good funds right now. Should I follow that?
sorry for misspelling “explain” in first part of the question.
Here are some more details: I am 34 years old, and I have invested in the dividend yield funds solely because of their good history of returns. My aim is to receive good return after say 20 years.