Of course you can nail them, mortise and tendon them, biscuit joint them, use splines, dowel them, use corragated miter nails, use nothing but glue, use only nails and the list goes on.
Pocket screws are great but the joint is only as good as your clamping holding the joint together before you drive the screw. If the wood is misaligned or slips while you are driving the screw the joint will suffer.
Norm of Old Yankee Workshop fame built everything with glue and nail gun, that is until the "purist" complained about his use of nails. Then he went to mortise and tendons, biscuits or some other joint. However everytime he had a chance he slipped in the old trusty nail gun.
The biggest thing you want to do is make sure whatever you do leaves a pleasing look. Beautiful wood can look ugly if you see a jambled bunch of nails holding it together, or a misaligned joint or sloppy glue joint.
Take your time, work at you pace and use what you have available.
Woodworking is very forgiving and I believe real craftsman ship is the ability to cover oops, ah hecks, and other stupid mistakes.
I once built a set of three end tables using fairly expensive wood. When I got done they looked like engine stands.
I was this close .. to taking them and burning them.
Then I got in recovery mode and by cutting down the size of the legs, putting a few fancy edges and chaffering a little wood here and a little there they turned out very nice, even if I do say so myself.
Take you time and remember not to be too hard on yourself.
post some pictures!