Sorry to hear about your situation. For what it's worth, I personally know people who received an offer in later rounds (even up to round 5!). So, in all honesty, it
is possible. This is especially true since some students will decline their offer since they got an offer interstate, changed their minds, etc.
Undergrad isn't your only pathway into medicine (and becoming a doctor), and from what I've read, I'm sure you are aware of the graduate options available. It does suck to not to receive the offer you wanted, but please remember this doesn't mean you aren't cut out for medicine or being a doctor - unfortunately it's just the reality that there aren't enough places for everyone. Nonetheless, don't let this be the end of the road for you - there is plenty of advice (and success stories!) out there of people who have been in your exact situation and ended up where they wanted to be (albeit a slight detour).
I understand that you might not feel comfortable discussing this with people in your life right now, but don't forget that they're there to support you (regardless of what happens next). It's important to talk about this to someone you trust, especially since this is an important time for you right now. To reiterate, this isn't the end of the road

Hang in there!