Maybe it depends on how strong you are to do them. So my answer is no it may not be safe.
because exercise makes blood pumps around the body faster therefore with less blood some parts of your body become starved of oxygen
You should see the doctor. It might just be caused by lifting something very heavy but it could be worse.
heavy lifters ( most of them were slaves )
"heavy lifting"
Befopre you lift a heavy object:understand the weight of the objectGet help in lifting it if necessaryassume an appropriate posture for lifting
For lifting and stacking heavy objects
It provides heavy lifting.
For lifting and stacking heavy loads.
Lifting heavy stuff
Bend your knees.
Heavy lifting
Lifting shorts are good when lifting weights because they provide the lifter with protection and support from injuries. They are a good idea to have when doing heavy lifting.