The element variable {ce_first} is parsed inside every element and will be true (1) or false (empty) in a conditional to indicate if it is the first element for this entry.
Simplified case example:
{exp:channel:entries channel="your_channel" limit="10"}
{custom_field}
{heading}
{value}
<p>{if ce_first}This entry has <strong>{ce_count}</strong> elements.{/if}</p>
{/heading}
{/custom_field}
{/exp:channel:entries}