Position Vs. Time Graph (Activity)

In the running activity, we recorded the distance we ran and the time it took to run it. The relationship between position and time allows us to get our velocity and our acceleration. The time it took me to reach each checkpoint was fairly constant at the end, but the begining part had some variations. The initial velocity was 0 m/s the ending velocity was 5m/s. However, from 0-2 seconds the velocity changed to 2.5 m/s. because of that change, acceleration is created. My accleration from 0-2 seconds/ 0-5 meters was 0.5m/s^2. My acceleration changed however, and remained constant for the rest of the data. From 2-6 seconds/ 5-25 meters my acceleration changed to 0.625m/s^2. After that Acceleration change, there is no more acceleration because the velocity remains constant. The velocity from 3 seconds onwards is 5m/s. It is constant therefore no acceleration. These are the conclusions I came to looking at my graph according to my running period.