Hi krystal,
Nicola and Florencia gave you some good advice, what does your doctor say about night feeds? If he doesn't need to feed at night, one way to wean him AND make sure his blood sugar stays relatively stable is to cut out a feed every every 3 nights, and then adjust his food intake during the day. Cold turkey is usually the way to wean older toddlers, but depending on what your doctor says, this might not be the best for your son because of a big fluctuation in blood sugar levels. So at first you could do a late evening feed (before midnight) and an early morning feed (around 4 am), but try to cut out the one around 1-2 am. Then once that one is dropped, you could try cutting out the late evening feed, or shifting it a bit earlier. Then after a few days you could work on shifting the early morning feed back later.
If he does need to feed during the night could you replace 1-2 night breastfeeds with a cup of fluid instead?
Could you get someone else to help you for a few days? Or try dropping the first feed over a weekend or when your husband doesn't have to work? It really is easier to wean if someone else goes to your son in the middle of the night. Otherwise he might get really confused about why you breastfeed him at some times and not at others.
I think it would help to have a talk with him first before you stop the feeds, explain to him that the doctor says he is old enough now not to nurse during the night and you are going to help him learn to sleep. In the last BW book there is story on how Tracy helped a family with a nursing and co-sleeping toddler which might help you, but it required Dad to help out a lot!
Finally, to let him know when it's time for the early morning feed, you could try one of those silent alarm clocks, I've seen ones with bunny ears that pop-up instaed of an alarm. Explain to him that it's not time for a feed until the ears pop-up - he should be old enough to understand. When he wakes up in the night for a feed explain to him that the clock says it's not time for a nurse yet, and he should go back to sleep. YOu might have to pick up/put down to help him get back to sleep though.