Lots of good advice here, although you do need to be careful about over-the-counter medicines - it would be wise to check with your AME prior to use as some are prohibited for pilots.
On a purely practical note, it would help if you avoided the thermally active part of the day and booked to fly either in the early morning or late afternoon/evening when the atmosphere is more stable. The smoother air should help with motion sickness and you will get the feel of the aircraft more easily if it is only your control inputs which are affecting the aircraft, rather than external air movements.
In a nutshell: perfectly normal, persevere and it will go away
