To have asked the question suggests that you might want to do it just to be confident. Required vs Prudent are two different animals. Required usually revolves around a specification or a code. Prudent is - am I bothered?
Slopes in cohesionless materials will be of an infinite slope variety - the worse case is a thin laminar sliding. We usually look at the situation and say - "well, what amount of soil could we tolerate to "move"?" Usually we would pick 10 ft or so and ensure that the sliding plane was at least that thick - this would give you a handle on the sensitivity of the slope. You never said how close your footing was or what it was to support - that might be important too. At 14 deg angle, even if fully saturated, it should be stable but it takes only a few minutes to carry out a quick analysis to ease your mind . . .
