Congratulations on your new little one!!
I'm so sorry about your mare rejecting it though. I'm glad you were able to milk her and get your baby the colostrum it needs, as Chanda said you'll need to be ready to continue that. You'll need to feed regularly every 2 hours. Milk as much colostrum as you can and store it. You may have to restrain the mare, tie one of her back feet up each time, use a corral panel to hold her against a wall,.. and possibly also use a mild tranquilizer for a few days. Once the milk makes it through the foal then the mare will recognize the smell and sometimes bond with the baby at that time. I also agree with giving her a dose of oxytocin, if your Vet agrees with it.
I recommend giving the mare a dose of Banamine immediately after her first stool (and a dose of Ivermectin). Some mares do NOT handle pain well... she has given birth, will have an engorged udder, and contractions for hours to days afterward to first expel the placenta and then shrink the uterus back to normal so she needs something for pain.
I would advise you (everyone) to leave the bedding there that she foaled in, the mare needs that smell as it's from her and the foal is covered in it....(probably needless to say but I don't mean leave it forever, just until all is ok). I always recommend to Not dry the foal immediately nor put a foal blanket on it...and always leave the placenta there for a little while. I did, however, use a towel for my own hands when I had to assist with the foal and if I did then I'd rub that on the mare so if you still have any of that you may try handling it then rub your hands on the foal and mare. I don't know how your mare reacted but most mares are instantly drawn to the smell of the sack and the foal.. was she? or did she see the foal moving and get scared so never smelled it or licked it at all? Some maidens are totally scared of that little thing suddenly there and will react violently, it just happens there is nothing you did wrong.
Continue to milk and feed, usually once she learns that the foal nursing relieves the pressure of her full udder she may accept it.
If you have another mare close by you can try leading it by the stall to see if there is any mothering instinct there...if so it may help kick her into protection mode. As far as the tall baby, sometimes it takes them a while but if you can keep the mare still the foal will be able to nurse from her, don't worry about that.
Pictures??? please.