If I remember correctly SA recurve crossbows are recommended having the string changed every year. With the low velocity of 200 fps arrow drop will become a factor and shooting from an elevated position will have different POI than shooting from the ground.
Try practicing from the height you hunt at and make the necessary adjustments. I would also recommend saving up for another crossbow for next year. I have shot that crossbow next to my Tenpoint GT Flex and there is a noticeable difference in construction, velocity, and accuracy between the two.