if in doubt - call atc
like others have said - best to call up as soon as poss - frankly id rather earn my cash helping you out than putting out a call to search and rescue saying i think i just lost one
and yeah - we may end up holding the " big boys" to get you in - but emergency traffic takes priority over everything else
dunno about the costs etc - but - i would hope that wouldnt be a consideration as to whether you would declare an emergency or not
folk do make mistakes - and as we all know the weather can suddenly get a bit crap unexpectedly, - had a snow warning come out once about an hour after it had started snowing!!!!
enjoy your flying!!!
yaffs