Extreme fatigue at 29/30weeks


So I am extremely constantly fatigued and sleepy. I sleep all night till 9am then I sleep off again around 2pm till 6pm then force myself to stay away. My legs really hurt when I stand up for more than 2mins. Is anyone going through this type of fatigue and sleep at this stage in pregnancy pls? Is it normal and how do I fix it pls? Cause it is stopping me from doing my daily activities.