Strange, this one.
Epaulets of a Lieutenant between 1815 and 1830. The Ulan style collet and blue shoulder straps with regimental number indicate the 34. Landwehr-Kavallerie-Regiment, formed in 1817, and reduced to a reserve squadron in 1819.
However, according to Mila and Pietsch (the latter possibly just copying Mila), this regiment's s collars and buttons were white, which from 1819 was changed to karmoisin (crimson) red collars, still with white buttons. Schulenkamp's ponceau red collar with yelllow buttons would match perfectly with the 34. Landwehr-Infanterie-Regiment (reduced to a reserve battalion in 1819), but the Ulan style collet does not.
The medal is the Kriegsdenkmünze, given to all Prussian combatants of the 1813 to 185 campaigns. There were no Prussian medals for certain battles (single exception is the Kulmer Kreuz, given to all Russian - but no the Prussian - participants of the battle of Kulm).