It sounds like this transition is much harder on you than it is on him.
Our first child was cared for in our home by a friend's mom until he was 21 months-old. We moved him to a traditional day care when he was 2 (along with his newborn sister) when I went back to work.
He didn't like the change, and it took a few weeks to transition. Both were OK within minutes of us leaving. But, despite being there 2 years, our son still has a hard time transitioning to new classes within the same facility. He's a creature of habit, and it's harder on him than his 2 year-old sister.
I'd give it some more time. My best advice is simply to drop him off, say good bye, leave, and let the caregiver make him comfortable. He is happy to see you at pick-up and misses you - that's likely why he's getting upset then.
Cherish the moments you do have with him and make the most of them.
Good luck!