just something that works well for me--
i breastfeed before i give my son solids. he is the same age. Breastmilk is the best thing for him, you'll know he is getting a full feeding, and then whatever solids he eats after is the supplement. If you aren't trying to wean him yet (you still have 5 months), breastfeed just as often as you did before you started the solids. (I know sometimes it might seem nice to have a break, but you won't worry this way, right?) I've noticed with my son he is so interested in anything different, especially if we don't offer it to him, so maybe put the cup (empty), on the floor with him for a few days, let him get acquainted with it and interested by it.... but really, it has been best for me to breastfeed first before solids. (i personally don't ascribe to the idea that a baby needs something to wash down the solids-- if he is thirsty, breastfeed him after, but he doesn't have to have water).... oh, and btw-- my son won't take a bottle either, but where we are at in the breastfeeding relationship, that is fine for both of us. Good luck and if you want to empathize, message me, i totally get where you're at!