Seriously Losing time help!

[pestes]

Hello everyone first time poster here. Love your forum and have enjoyed reading everything here. I am the proud owner of a SS Submariner and a SS 1964 datejust.

I have recently purchased a TT Submariner mfg. date is 1991-1992. I took the Cape Cod cloth, etc to it and it looks like new! Much to my chagrin I started wearing it las night and the dang thing loses an absurd 1-2 seconds a minute!

I wound it and have worn it all morning and it is still losing 45 seconds or so every hour. (I am wincing when I say that)

So, I am looking for help, advice, anything you wonderful folks could send my way.....
-Do I give it back to him and demand my money back because the movement is really effed?
-Could it just be a bad mainspring?
-Do I need to wear it longer get it to "warm up"?

In addition, the crown winds very rough compared to my SS submariner IDK if that could have something to do with it. It undoubtedly needs to be serviced I am assuming but any help in the meantime from you pro's would be MUCH appreciated as I am worried I just purchased a bad Rolex.

Thank you!