Yes you are correct, if your reaction caused an increase in temperature, energy was released from the system into the surrounding and is an exothermic process. I am assuming the experiment is Calorimetry....This is straight from a chem textbook:
If so ...the walls of the calorimeter are insulated so that there is no exchange of heat with the air outside the calorimeter...it follows then that the only heat flow is between the reaction system and the calorimeter. The heat flow for the reaction system is equal in magnitude but opposite in sign to that for the calorimeter:
q rxn = -q calorimeter
Notice that if the reaction is exothermic (q rxn < 0), q calorimeter must be positive; that is, heat flows from the reaction mixture into the calorimeter.
Note: the rxn mixture is the system the calorimeter is the surroundings.
hope this is helpful!