Hmmmm.... Allow Healthy lifestyle with ideal posture during sitting & sleeping.
You have lost your endurance & coz of weigh poor posture lack of flexibility you are experiencing stiffness,pain & lethargy [Main cause is
Thyroid issue].
Follow some rules protocol strictly for 3-4 months atleast you will be fine & your thyroid level also will get down.
Use sports shoes & do ankle pumps a lot to reduce Cramps. Hydrate your body to decrease intensity of cramps.
You can use Epsom salt in water to relieve pain stiffness etc.issues.
God bless u
Next Steps
Rehydrate yourself properly.
Proper Diet plan should be taken care.
Do Some breathing exercises, Flexibility exercises low to moderate grade.
Brisk Walk is most important atleast for 30min twice in a day. which can increase with time.
Don't skip breakfast at all (Main cause of B.p. fluctuations).
Have proper sound sleep.
Can do some Yoga poses for
Thyroid issue after sometime(You can consult any Yoga guide once for it).
Health Tips
Don't use mob.while sleeping or lying down position.
Use proper pillow position while sleeping.
Use ergonomical design area while working or studying.