Transparency is the key. If you want to call him, call him. Tell him you are heartbroken without any contact. Don't apologize anymore for the mistaken temper flare that he already said he forgave you for. Now you have to forgive yourself. Reassure him of your continued care for him.
If you were as close as you say, you can bet he misses you too but you scared him a little. So don't do that again. Remember he has feelings too & take care of them. Treasure him. Take it slow.
I wish you the best in this ...