Going by the information supplied... I'd say not gravid.
Here's why.
"in early i sept i put my male boa dagda in with my female vesta.
they mated."
OK, this part sounds good. He was breeding during the right time of year.
"he stopped the first week of nov."
OK, this part also sounds good. He was breeding then he lost interest. That's "normally" the way it goes. I have to wonder if you removed him from her cage at this point......
"she refused to eat nov, then again in dec.
she shed in dec."
Once again.... This part sounds good. I always look for that refusing food from the female, to know that she's going to ovulate soon. Then she had a shed "after" your male lost interest, so "in theory" this is good sign.
"then ate a small rat which left a lump.(from the photo you can tell a small rat really shouldnt do any thing)"
This is good. My females always take a meal after the POS.
"jan she refused to eat."
Refusing food doesn't mean gravid, but since "some" female stop eating after they're gravid... This sounds good.
"march she ate a small rat(left another lump)"
OK, you fed her in "March"???? OK, lets do some math. She was in with the male in sept. He lost interest in Nov. She shed in Dec... You didn't say the date, so I'll figure it was Mid-Dec. So... We count 15 weeks from Dec 15th...... That comes out to March 30th for a due date. Can you see why I say not gravid? Sooooooo, let refigure it.
"march 16 she shed."
OK, another shed. Gravid boas do shed, but... I really don't think she's gravid. This is probably just a shed.
"april she refused to eat."
Once again... This is a sign I look for, that a female is going to ovulate. My females always refuse food when they're gong to ovualte.
"she does have a slight lump."
My females always have a slight lump when they refuse food. My theory is that folicles are forming, so there's a "slight lump or firmness". Not a swelling, but a lump. Sort of like they ate a small meal, only they didn't and there's a lump there.
"this month may 7 she ate a small rat had a huge lump this time."
Well, small rats won't make a "huge lump"...... However.... This huge lump, "could" have been an ovulation. If you removed the male back in Nov..... Well, she's not gravid. Unless, she manages to retain sperm.
"the temp in the enclosure is 90 i catch her during the day going to the cooler side which is in the 80s."
Cage temps are good. Gravid females "normally" stayed coiled up to stay warm. If you have a temp gun, you can check her temperature. A gravid female will be between 86 and 88 degrees. Of course, a boa that's not gravid could also be that warm, since your temps are 90 on the warm end.
"im guessing shes gravid but i know i could be wrong aswell."
I'm still guessing she's not gravid. I hope I'm wrong, but from the info you've given... She should have had them by now.
"please note the photo was taken before the breeding ever occured"
Do you have any pictures of what she looks like now??
Anyway, you didn't say if you removed the male. If you removed the male in Nov... It's more likely that's she's not gravid.
Do you have anymore info that would be helpful? Why are you guessing she's gravid? Has her behaviour changed? Is her rear half very swollen?? Did you figure out a due date? Did you see actual copulation or just him "courting"?