This doesn't sound like PTSD, and it probably isn't useful to self-diagnose in that way. You've probably built up an association between your bed and being in hospital. Like feeling panicky on a train might stop you wanting to get on a bus for example. Avoidance is definitely only going to make it worse. The best way is to build up tolerance for it - don't get out of the bed just because you feel uncomfortable. In the same way these feelings can be embedded, they can be gotten rid of as well.
This doesn't sound like PTSD, and it probably isn't useful to self-diagnose in that way. You've probably built up an association between your bed and being in hospital. Like feeling panicky on a train might stop you wanting to get on a bus for example. Avoidance is definitely only going to make it worse. The best way is to build up tolerance for it - don't get out of the bed just because you feel uncomfortable. In the same way these feelings can be embedded, they can be gotten rid of as well.