In this article, we present the systematic relations, both at concept and syntactic level, between the spatial sense of going beyond a point in space and the metaphoric sense of excessive quality in a syntactic pattern which in Spanish includes the formal reflexive verb "pasarse", within the framework of Cognitive Linguistics. We present the theoretical principles of this approach and characterise the descriptive tools used: image schemes, conceptual metaphor, and mainly force dynamics. We also show that the latter permits the explanation of the use of the reflexive form encodes the fact that the expectation imposed for both senses is not fulfilled: in the spatial sense of 'pasarse de largo', the expectation that a moving object must stop at some reference point and, in the metaphorical sense of 'excessive quality' ("pasarse de bueno"), the expectation that the quality must not exceed a certain degree of normality.