What can I expect specifically from getting the injection for a chalazion? How soon after can I wear makeup? (Photo)

Generally it will be associated with some discomfort and swelling.  You can bruise.  Depending on the nature of these post procedure issues it could take several days but up to a week for this to settle down.  The injection can take severally weeks to heal.  I generally reassess these after 4 to 6 weeks.  If the injection helped the chalazia but it is not full resolve, I will repeat the injection.  Surgery is seldom necessary.

How long have you had the chalazion?  Usually best to treat conservatively.  Warm compresses.  Can try steroid injection first.  If this doesn't work, and chalazion persists beyond 2-3 months can consider surgical excision from inside the lid.  Usually get pretty swollen and bruised with this.  But can wear makeup after a week.  

eyelid surgery : chalazionyou may heal from this or may need antibiotics and an incision inside the lid to remove the chalazion