38 weeks pampering

I have scheduled myself to get pampered (mani , pedi and eyebrows done ) when I am 38 weeks since at 39 weeks I will be having my c section . The eyebrows to get done Is about a 45 min appt but I need to lay on my back , I’m not sure if I should just cancel my appt or it’s safe to lay on my back for that amount of time ?

I just want to look and feel semi good about myself since this past year with covid i have not gone to get pampered. Or should I just ask my dr if it’s safe to lay straight on my back for that amount of time ?