Feeling some kind of pressure and pain is normal for initial few days of crown placement as crown requires some amount of time to adjust.

You will also feel some cold sensation...so take care not to eat too hard or bite on anything hard from that tooth...maintain proper oral hygiene by doing warm saline gargles, brushing twice with soft bristles brush...Also take the medications as prescribed and apply a layer of tooth paste, leave it for 10 minutes and wash it away...it will provide you with some relief...for more info visit the link....http://www.identalhub.com/article_complications-and-care-after-root-canal-therapy-106.aspx