Hi My Fiancé Is 39 And In Very Good Shape,

hi my fiancé is 39 and in very good shape, exercises a lot and eats well. For the past 2 days however his semen is kinda orange in colour- he reports having no pain or discomfort- is this any cause for concern- he does mention urinating after is slightly burning- when do we get worried? Should he rather just have a check up?