This can be a natural reaction to the injection site. If it does not go away in 48 hours, contact the doctor. It could be the result of an allergic reaction to components of the shot.
The lump most probably is a blood clot that developed after the shots were given. If it doesn't subside, gets bigger or infected it is better to get an assessment.
Swelling is a common reaction to typical shots and vaccines. Whiles shots are incredibly safe it is important to remember that they do create an injury and like other injuries your body wants to protect itself. The swelling will go down in a day or two.