Fussy baby....

I have no idea what's going on, but for the last three days my son has become super fussy when I try to breastfeed him and he's been wanting to feed more or less constantly. However, when I give him his nightly bottle, he's happy.

I'm thinking it could be either:
-the heat (it's REALLY hot here right now)
-not going on our daily walks because of the heat
-my period started and I read somewhere that can cause milk production to drop and for it to taste different
-teething (!?!??!) - he's chewing on everything suddenly
-another growth spurt????(he'll be three months on Wednesday)

Up until now, I've been breastfeeding plus giving one bottle at night (his night-time feeding). Now I'm thinking I'll add another bottle to the mix to make sure he's getting enough. But I'm worried that by dropping one more BF feeding my milk will dry up. Does anybody know if it will? Did any of your babies get fussy around this age? What caused it? Any suggestions/advice would be appreciated.  

Quoting scubakitty:“ I have no idea what's going on, but for the last three days my son has become super fussy when I try ... [snip!] ... if it will? Did any of your babies get fussy around this age? What caused it? Any suggestions/advice would be appreciated.  ”

you seem to have some good ideas as to why he's fussy,
thats what i would have said.
as to drying up, get a pump and pump at the time you'd normally feed him.