Sea Fishing Newbie!

Hello - I'm used to fresh water fishing and so this sea fishing malarky is
quite a different kettle of fish for me! I've just got a question about why
my reel seems to continually get in a tangle with line spooling off on a
cast out into a bloody big time-wasting bird's nest at least two or three
times a session. Do you think its got anything to do with extra wind from
the sea or the weight of the tackle (maybe underweight), etc, rather than
just me being crap (this never used to happen on fresh water casting this
frequently!). So far, I'm really only spinning from the shore with a
pike-lure sized spinner.

Cheers for any advice!