Yes. Lack of adequate rest can put one off sexual feelings and erections. Binge drinking is also harmful. so may be due to these combined reasons you are not seeing the erections.
Next Steps
The human body prioritizes the importance a sper your mental frame. Right now you were busy with the college things and hence it kept sex on back burner to conserve your energy. Once you are out of this busy schedule the erections will happen on its own. Give it some time