Yes, as of May 25 photographers also became obligated to comply with the GDPR. Although you have already been obliged to do many things within the framework of strict German laws, from May 25 data processing that does not comply with the GDPR may result in harsh penalties.
We would be happy to advise you here, but unfortunately, we are not lawyers. Therefore, we ask you to contact your lawyer or a professional consultant for the necessary updates of your website, contract templates, etc. A first step for the rough understanding of GDPR can be found on the Podcast "Uncle Bobcast"  by wedding photographers by Nils Hasenau and Manuel Gutjahr. They spoke with an attorney on the topic of GDPR. (German)