I'm completely exhausted from the first day of Pilates. Can I survive with just one diet shake?

Maybe it's because it's winter, but I just want to crawl under the covers and my body feels heavy. How are you all taking care of yourself in this cold weather? I finally signed up for Pilates today and went to my first class, but right now my whole body aches so much I can barely type! It's below freezing outside, so I'm shivering, but I worked out in the air from the indoor heater, so I'm sweating... I'm so exhausted I skipped lunch. It's 1:30 PM right now, and I'm hungry, but I have absolutely no energy to cook, so I'm debating whether or not to grab one of those diet shakes I had on the shelf. Honestly, the workout was so intense I doubt a diet shake will fill me up... Do you guys manage to stick to just this when you're planning your post-workout meals? Or can you recommend a high-protein diet shake that's a great meal replacement? I'd prefer something with a slightly chewy texture, rather than something too light. It would be even better if it had a flavor strong enough to resist the temptation of tangerines or bungeoppang! I've been feeling this way since day one, so I'm worried about the future. Veteran members, please share some of your tips! I have so many questions, and I'm so hungry and curious right now...!