Getting to understand patterns and causes of motivational changes experienced by language learners while studying a foreign language can be of significant value. This paper aims to explore patterns of such fluctuations at the tertiary level. Through a dynamic systems perspective, this study employed Retrodictive Qualitative Modelling to generate the learner prototypes. The data were then collected from two distinct cases that represent different motivational prototypes. While the first one manages to have a highly intense goal-directed motivation (Directed Motivational Currents- DMC), the second one does not seem to have DMC. Data concerning ebbs and flows of learners' motivation and affective states in the classes were collected through self-plotted motigraphs over six weeks. The results showed a significant difference between the motivational patterns in the two learners. The first one with an identifiable DMC displayed a more stable pattern on the motigraph and the other one drifted aimlessly without a clear focus. The findings of this preliminary study will be discussed in relation to dynamic theories of motivation. Suggestions for further research will be offered.