does it matter if i plug a hdd into a different sata port on my motherboard?

Solution
No, it won't make any difference. You're motherboard will detect the change and should recognize it's the same HDD, so it will still have the same drive letter.
the only time it might make a difference is is you were using raid.
or if you were gonna plug in another drive that also has an o.s in the original slot while moving your old hdd to a new 1.. as that would upset the boot priority in bios (you just change it over 1s installed)