I'm going to list these workouts consecutively but feel free to split them up however best works with your week. If at any time you start to feel pain, faint, or dizziness stop right away. You should never feel sharp pain when exercising, so make sure to listen to your body (discomfort and muscle fatigue is different).
Monday
Upper Body
You will need your dumbbells and a chair or a bench. You want your weights to be heavy enough that you're feeling fatigued by 12-15 reps. If you feel like 15+ reps is really easy, you may want to consider bumping up your weight.
This workout will be setup as a circuit, meaning you'll do each exercise one after the other without rest. Once you get through the entire first circuit, you'll rest for 1 minute and then start on the second circuit. Each of these exercises links to a youtube video that shows the proper way to perform them. Not having the correct form puts you at risk for injury and doesn't isolate the muscle properly, so be very mindful as you're exercising. Again, a mirror if you have one is a great idea to use!
Warm-Up
Circuit 1
Rest 1 minute
Circuit 2
Chest Press 12 reps (If you don't have a bench or a stability ball, doing this lying on the floor, with knees bent is just fine.)
Lateral Raises 12 reps (Use a lighter weight for this exercise and really focus on form)
Cooldown
Here
Tuesday
Today is a cardio day. It will be low-intesity and kept at a moderate pace for the duration. You can do either the elliptical or bike at a challenging level that you can sustain for 30 minutes. You shouldn't be completely out of breath but you also shouldn't be able to easily carry on a conversation.
Wednesday
Lower Body
We're sticking with the circuit set-up. You will not need any equipment for this workout.
Warm-Up--perform each move for 30 seconds
Jumping Jacks
High Knees
Squats
Circuit 1
Circuit 2
Calf Raises 20 reps
Cooldown
Thursday
You made it to your last workout of the week! Today, you're going to finish strong with some High Intensity Interval Training, or HIIT cardio. This will be short and intense to reap the most benefits. So dig deep!
20-Minute Elliptical Workout-- Here