When you go for USPHS - when do you get your physical?

You can choose to go to a MEPS, or your own private physician-at your own cost. You can go anytime you like, but you cannot get orders until you are medically cleared, so-the earlier you go, the better. But there is no "set time." You have to clear all three areas nursing board, security, and medical to be complete.

Are the physical requirements and weight restrictions the same as for active duty?

Yes; you must meet weight requirements, or meet body fat percenatges as calculated by the Navy method. If you do not, you still can get in, you just will be on a limited medical tour for a specified amount of time, which will give you time to get your weight within control. You will be required to make progress at specific intervals. I know all this because I am anemic, and I am over their weight standards by six pounds. But I met the body fat percentage requirements. I am on a limited medical tour for the anemia.

im 5'4" and the 140lbs. the max is 163lbs for my height, would they make a big deal out of that like tell me to gain some weight or am i fine as it is?

No. As long as you dont pass the limit, youre fine.

I think its 10% within the weight standards