hi guys

hoping somebody can help

on saturday i noticed the temperature gauge start to act a little funny
when i first turned on the ignition the temperature gauge went upto around 70 even before id started the engine
the temperature climbs and eventually hits 90 degrees and usually stays there
however on the way home it went up to around 100 and then went back down to around 90 again then started dropping slowly
towards 70 again

has anybody had similar issues ??? and if so how did they cure this ?