My cat has been vomiting quite a bit over the course of yesterday and today. I have thoughts it could be Gastritis but I'm unsure. I don't know what to do, and need someone's opinion of this.

Explanation:

u should take him or her to the vet 2 see what wrong he might have something wrong its system i did this 2 my cat and it helped

it probably is gastritis.

Gastritis is defined as inflammation of the lining of the stomach. It may occur as a short episode (acute) or have a long duration (chronic)

The most common clinical signs associated with gastritis are sudden vomiting and decreased appetite (anorexia). Other clinical signs may include dehydration, lethargy or depression, increased thirst, blood in the vomit or feces, and abdominal pain and also vomiting.

Acute gastritis occurs more frequently in kittens, or in curious cats, who eat things they should not eat (dietary indiscretion).

Explanation:

some non medical ways to treat her may be

withholding food for 8-12 hours

offering small amounts of water frequently during the first 24 hours. Note: If fluids cannot be given orally without inducing vomiting, seek immediate veterinary treatment

if there is no vomiting, feed a small amount of a highly-digestible, low-fat food

resume feeding with small meals given frequently (usually about ½ of the normal daily amount of food, divided into 4-6 meals)

gradually increase the amount of food over the next two to three days

if vomiting returns, notify your veterinarian

hope this helps and i hope she/he feels better!