All too familiar
I crashed last February and suffered 4 broken ribs, a punctured lung, and broken clavicle. I wasn't going anywhere near 38MPH, but the damage was done. Five days in the hospital with a tube in my side to bleed the air out that escaped the lung when it punctured. The clavicle was fixed three weeks later. But...I was back on the bike in a few months, but only an indoor smart bike. Two ribs healed in a very precarious position and I can't risk falling on them again. If they break, they'd likely hit a blood vessel and I'd bleed out.
Anyway, follow the doc's advice, and don't rush things! It takes time and in the end it will be worth it. If you can, consider an indoor trainer if possible. Not road riding, but way better than nothing.