What does an infant seizure look like?

My 7 month old daughter has me concerned that she is having seizures...she has always 'bike peddled' her legs and flailed her arms when excited, but recently she has began 'lip smacking' and moving her head left to right in repetition randomly. Everyone I talk to about this seems to think she's just acting normal...is this the case and I'm just a 'worrywart' or is this something I should be concerned about? HELP!